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A256603 Numbers D such that D^2 = A^3 + B^4 + C^5 has more than one solution in positive integers (A, B, C). 5

%I #22 Jan 07 2016 19:14:26

%S 305,525,1206,1257,1395,2048,2213,3072,4348,6400,16385,16640,16704,

%T 20631,22872,23256,30968,31407,32769,62943,74515,77713,77824,79776,

%U 82565,84775,90432,98739,117600,121250,133696,163525,165628,171576,198400,199872,243225

%N Numbers D such that D^2 = A^3 + B^4 + C^5 has more than one solution in positive integers (A, B, C).

%C A subsequence of A256091. Sequences A256604 and A256652 are the analog for A180241 and A255830.

%H Chai Wah Wu, <a href="/A256603/b256603.txt">Table of n, a(n) for n = 1..185</a>

%e (A, B, C) = (32, 128, 1): 32^3 + 128^4 + 1^5 = 32768 + 268435456 + 1 = 268468225 = 16385^2

%e (A, B, C) = (1, 128, 8): 1^3 + 128^4 + 8^5 = 1 + 268435456 + 32768 = 268468225 = 16385^2

%e so 16385 is a term.

%o (PARI) for(D=1,9999,f=-1;for(C=1,sqrtn(D^2-1,5),for(B=1,sqrtn(D^2-C^5-.5,4),ispower(D^2-C^5-B^4,3)&&f++&print1(D",")+next(3))))

%Y Cf. A180241, A180242, A255830, A256091, A256604, A256613, A256652.

%K nonn

%O 1,1

%A _M. F. Hasler_, Apr 06 2015

%E Inserted a(11),a(16) and added a(19)-a(37) by _Lars Blomberg_, Apr 17 2015

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Last modified April 20 07:43 EDT 2024. Contains 371799 sequences. (Running on oeis4.)