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%I #14 Jan 20 2020 12:53:47
%S 1,1,3,2,1,3,7,8,7,1,13,6,15,15,12,16,16,2,10,20,18,21,7,16,9,22,13,
%T 22,23,24,20,10,25,12,25,22,26,27,11,26,28,30,27,31,22,31,34,30,35,36,
%U 28,31,37,8,37,16,27,36,35,40,1,3,13,31,37,28,33,42,21
%N a(n) is the least positive k such that A100271(n) - k^3 is a fourth power.
%H Rémy Sigrist, <a href="/A331523/b331523.txt">Table of n, a(n) for n = 1..10000</a>
%H Rémy Sigrist, <a href="/A331523/a331523.gp.txt">PARI program for A331523</a>
%e The first terms, alongside A100271(n), are:
%e n a(n) A100271(n)
%e -- ---- ----------------
%e 1 1 2 = 1^3 + 1^4
%e 2 1 17 = 1^3 + 2^4
%e 3 3 43 = 3^3 + 2^4
%e 4 2 89 = 2^3 + 3^4
%e 5 1 257 = 1^3 + 4^4
%e 6 3 283 = 3^3 + 4^4
%e 7 7 359 = 7^3 + 2^4
%e 8 8 593 = 8^3 + 3^4
%e 9 7 599 = 7^3 + 4^4
%e 10 1 1297 = 1^3 + 6^4
%o (PARI) See Links section.
%Y See A331435 for similar sequences.
%Y Cf. A000583, A100271.
%K nonn
%O 1,3
%A _Rémy Sigrist_, Jan 19 2020