٥륯åĥ
դĹ򢢡+++ȤȡѷˤʤˤϢ䢤Ǥɬפ롣
233ޤǤϤ줾좤1̤꤫32̤ꡣ
3497ϡ줾좤323231312211̤ʤΤ
1+32ˡ32231584̤ꡣ
1124ڡ 0:10:32 45543
å
ѷʤȤȤǡ1584ѷʤ1683ʤҤäޤ(
1124ڡ 0:18:29 45544
Ȥ

Basic

AB=c,AC=b,BC=aȤ

for c=1 to 99
for b=c+1 to 99
for a=b+1 to 99
if a-b<>b-c or b+c<=a then goto 10
let s=s+1
10 next a
20 next b
30 next c
print s
end

f9ơ1584()

<100ʤΤ99Ǥʤ100ȤƤ٤ޤ2ʬ餤ǤǤäΤǤ
˭ԡ 1124ڡ 0:32:41 45545
ǯ
­˼ּޤǸϥ­
AB=aȤ롣aʾˤʤȻѷǤʤ
ξǡBC100̤ʤΤǡa99-2*ޤǤѷǤϰϤʤΤ
1λa297ǽ
2ʤ顢a395ǽ
13롣
96+93+90+....3=1584

1124ڡ 0:39:02 45546
¤ä
ѷΩϡա¾դ¡ꡢ
դxĹκyȤȡ
(x-y)+(x-2y)x äx3y
y=1λx4 x199顡
ߤxͤϡ96
y=2λx7 顡93
...
y=32 λx97 顡3
äơ뻰ѷθĿϡ
96+93+90+...+6+3=9916=1584
θ 1124ڡ 0:30:41 45547
ߤ
Ĺλʣ
Ĺλʣ
Ĺλʣ
Ĺλʣˡʣ
ĤȤäˤȤꤢĴ٤ȡ
Ĺλƣ̤ꡡף
Ĺλƣ̤ꡡף
Ĺλƣ̤ꡡף
ά
Ĺλƣ̤ꡡף
Τ褦ʵ§Ǥʬ롣

ȤϽࣳ򣹣ޤ­碌Ф
ʣܣˡߣࣲᣱ
1124ڡ 1:14:24 45549
kyorofumi
count = 0;

for ab = 1:99
for ac = ab:99
for bc = ac:99
if ab < ac && ac < bc
if (ab+ac) > bc && abs(bc-ac) == abs(ac-ab)
count = count+1;
end
end
end
end
end
1124ڡ 0:32:27 45550
鯤ο
AB=x,AC=x+a,BC=x+2a
ȤȡѷǤϡ
AB+ACBC顢
x1ġ1ax-1ġx+2a99Ȥʤ(x,a)Ȥ߹碌뤳Ȥˡ
x=1ΤȤaϤʤ
2x33ΤȤa=1x-1
34x97ΤȤa=1[(99-x)/2]
98xΤȤaϤʤ

ο1+2++32+32+32++1+1
(1+32)*32/2*3
1584
1124ڡ 0:35:51 45552
kyorofumi
you didn't need the if condition...

count = 0;

for ab = 1:99
for ac = ab+1:99
for bc = ac+1:99
if (ab+ac) > bc && abs(bc-ac) == abs(ac-ab)
count = count+1;
end
end
end
end
1124ڡ 0:36:16 45553
Mr.ǥ
դʤդ1/3̤ǤлѷΤ
ΤΤϡդ499Ρ96̤
ΤΤϡդ799Ρ93̤
ΤΤϡդ1099Ρ90̤

32ΤΤϡդ9799Ρ3̤
ä
3+6++96=3*(32*33)/21584(̤
ȹͤޤ
1124ڡ 0:44:19 45554
⡼ޥ
ΤǤ^^;;

99-a+99-2a>=100
2*99-(99+1)>=3a98/3=32>=a32
2*98-(98+1)>=3a97/3=32>=a

2*k-(k+1)>=3a(k-1)/3>=a
k-1+k-2=k+1k=4
k=499
398(32++1)*3=16*33*3=1584


ꤦ뢤ο
96+95++2
=96*97/2-1
=4655
ʤ...^^;;
1124ڡ 0:46:31 45555

Ф
֤˺Ƥޤ(^_^;)
ߤ󤵤Ʊͤ˵§Ĵ٤Ʒ׻ޤ
1124ڡ 1:07:02 45556

#45549ߤ󤵤ƱĤĴ٤ƣĤģ̤꤫飳̤ޤǤ̤꤬ʤȤ˵§ߤĤ׻ޤ
Ϻꡡ 1124ڡ 1:07:20 45557
Ȥ
#45545

ʥ쥹Ǥޤ󽽿Basic ǥɤûʤ

for c=1 to 99
for b=c+1 to 99
for a=b+1 to 99
if a-b=b-c and b+c>a then let s=s+1
next a
next b
next c
print s
end

XMaxima Ǥ3ԤǤ

j:0$for c:1 thru 99 do
for b:c+1 thru 99 do
for a:b+1 thru 99 do (if a-b=b-c and b+c>a then j:j+1)$j;

󥿡ơ1584()
˭ԡ 1124ڡ 1:32:45 MAIL:fttnm528@ybb.ne.jp 45558
mun
Ϥ褦ޤ

AC-AB=BC-AC=sȤȡ
0<AB, AB+2s<100.
ѷˤʤAB+AC>BC顢
AB+(AB+s)>AB+2s.򤤤AB>s.
ʾ夫顢
s=nΤȤxn+199-2n͡Ĥޤ99-3n̤ͤȤ
1s32
ʬޤäƦ^32_{n=1}(99-3n)=1584.Ȥޤ
1124ڡ 6:39:32 45559
ϥ饮㡼ƥ
ߤޤ󡡥ץǤ
1124ڡ 8:38:19 45561
ˤ
AB=a
b
BC<AB+ACa>b
BC<100a+2b<100äb32
b=1a=2,3,...,97
b=2a=3,4,...,95
...
...
b=32a=33,34,35
Ĥĸ
¤3+6+9+...+96=3i(1i32)=332332=1584
1124ڡ 10:01:13 MAIL:nikotan@fat.coara.or.jp 45562
???
k=0
for a=3 to 99
for b=2 to a-1
c=2*b-a
k=k-(1<=c and c<b and abs(a-b)<c and c<a+b)
next
next
msgbox k
1124ڡ 10:51:41 45563
̴
45554Mr.ǥͤƱͤǤޤǽʬ餺Ƚ񤭽ФԺäȤιͤ˻ޤޤ
1124ڡ 10:57:46 45564
uchinyan
Ϥˤϡơϡ
Ͽ޷δ򤷤οǤ͡
⥳ĥĴ٤е§ΤǡȤƤɸŪפʡ
Ū˲򤳤ȤȿؤݤʤäƤޤ褦Ǥʴǡ

BC - AC = AC - AB = cmȤޤ 1 ʾǤ
ȡAC = AB + BC = AC + = AB + * 2ǡ
BC < 100ꡤAB + * 2 <= 99 < 100AB <= 99 - * 2Ǥ
ǡѷΤǤꡤBC - AB < ACʤΤǡ * 2 < AB + < + 1 <= ABǤ
飲Ĥξꡤ + 1 <= AB <= 99 - * 2ȤʤꡤΤȤ1 <= <= 32Ǥ
ơξβ ABACBC ǡѷķꤷޤ
ǡ = 1 32 Ф AB ϡ(99 - * 2) - ( + 1) + 1 = 99 - * 3 ̤ꡤ¸ߤΤǡ
ǡ96 + 93 + 90 + + 9 + 6 + 3 = ((96 + 3) * 32)/2 = 1584 ̤ꡤˤʤޤ

껻Ūˤϡ 1, 2, 3, ȶŪĴ٤ 99 - * 3 ε§򸫤Ĥ롤ȤäȤǤ礦

̲ȤۤɤΤΤǤʤǤ˹ͤƤ⤤Ǥ͡

BC - AC = AC - ABꡤAC = (AB + BC)/2ȤʤꡤAB BC ϡξȤξȤǤ
ޤѷΤǤꡤBC - AB < AC = (AB + BC)/2ʤΤǡBC/3 < ABޤ
飲Ĥξꡤ
BC/3 < AB < AC = (AB + BC)/2 < BC < 100AB BC ϡξȤξȤ
ǤǡBC 3 99 ưĴ٤ȡ
03 04 05 06 07 08 09 90 91 92 93 94 95 96 97 98 99<--- BC
02 02 02 03 03 03 04 31 31 31 32 32 32 33 33 33 34<--- AB κǾ
00 01 01 01 02 02 02 29 30 30 30 31 31 31 32 32 32<--- ǽʾο
ޤǽ񤫤ʤȤ⵬§Ϥʬޤ͡
ɡ(1 + 2 + 3 + + 30 + 31 + 32) * 3 = (32 * 33)/2 * 3 = 1584 ̤ꡤˤʤޤ

Ū˽񤯤ȤǤޤ
6 ;Ǿʬˤʤꤽǡ㴳ݤˤʤꤽǤ
1124ڡ 13:24:27 45565
uchinyan
ǼĤɤߤޤ


ʲεҤϡ⤽ϻ伫ȤٶΥ˲᤮ʤΤǤ
޳ѤʤΤǤͤޤǤˤȻפäƸΤǤ
Ȥ⤢äơˡʬϻ F.A.Q. ΡֻϰϡפεҤ򻲹ͤˡ
ĿͤǤиǼŪ˹ԤäƤΤǤäơҴŪʤΤǤϤޤ
ޤǤ⤴ͤǤ餺

ʤؤݤΤ⤢ޤܤĤ֤ޤ
ޤΰαʤɤˤϡ줾Хꥨ󤬤ޤ

#45543#45552
ѷΣդ򡤢 + + + ȤơѷΩȢϰϤȤĴ٤ˡ

#45546#45547#45554#45559#45562#45564#45565Ⱦ#45568
BC - AC = AC - AB = ȤơѷΩȡϰϤȤĴ٤ˡ

#45549#45555#45556#45557#45565θȾ
BC 򤽤βǽϰϤưѷΩȤĴ٤ˡ

#45569
BC - AC = AC - AB = r ȤȻѷΩ狼 1 <= r < BC/3 뤳Ȥ BC ưĴ٤ˡ
#45546ʤɤ#45549ʤɤ碌褦ʲˡǤιʤޤʡȴޤ
ʤBC = 3n-23n-13n ΤȤϤ 1 <= r < n ȤʤΤ BC = 3n ξͤ 3 ܤФ褯
BC = 3n ξ n = 1 33 Ǿ r n ñ 1 33 ʣʤˣĤ٤ФΤǡ
33C2 * 3 = (33 * 32)/2 * 3 = 1584 ̤ꡤȴñ˵ޤ

#45545#45550#45558#45561#45563
ץˤˡ
1125ʶ 12:53:12 45566
ȡ衼ɡ
-衼ɡˤ褦ȻפäǤäưƣˤƤޤä
1124ڡ 15:36:45 45567
ȡ衼ɡ
λ96̤ꡢ2λ93̤ꡦȤ褦ǤǤޤ
1124ڡ 15:41:45 45568
ˤ⡼
ˤϡϰŻǰȯäΤ򤷤äǤ

ûդAĹդBȤơƱΤκȤ롣
BA+򡡤ģ1/3B

B99Bκ͡ˤΤȤϣ3232
B9832
B9732
B96ΤȤϡ3131

BᣳΤȤᣱ

Τ褦ˡB뤴ȤˡθĿäƤ
äơѷ¤ϡ

32+32+32+31+31+31+30+30+30++1+1+1

32331584̤
ʾ
޻Ա¶ʼΡˡ 1124ڡ 19:01:16 45569

ѷΩͤ˺졢ԤǤ( )
1124ڡ 21:20:20 45570
ޤ
򤷤­Ǥ(^^;
somewhere in the world 1124ڡ 22:33:39 45571
ʪ
#include<stdio.h>

int main(void){
int i,j,k,r=0;
for(i = 1;i <= 97;i++){
for(j = i+1;j <= 98;j++){
for(k = j+1;k <= 99;k++){
if(k-j == j-i && i+j > k){r++;}
}
}
}
printf("%d\n",r);
return 0;
}
ͤ⻰ѷΩ˺Ƥޤ^^;
2ŤޤޤΤǤդĹ1003ť롼פˤƤ⡹100ʤΤǤǽʬǤ礦^^;
1130ʿ 21:39:47 HomePage:Twitter45572