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%I #15 Jan 20 2020 12:53:57
%S 1,1,1,5,3,7,2,8,3,8,9,13,4,4,17,7,17,2,8,3,5,20,7,11,17,8,23,19,10,
%T 20,3,11,17,10,22,19,14,22,17,21,25,11,13,23,27,8,32,25,33,6,25,35,7,
%U 23,31,10,37,16,18,39,5,7,42,41,30,36,5,11,8,18,30,36
%N a(n) is the least positive k such that A006686(n) - k^8 is an eighth power.
%H Rémy Sigrist, <a href="/A331524/b331524.txt">Table of n, a(n) for n = 1..10000</a>
%H Rémy Sigrist, <a href="/A331524/a331524_1.gp.txt">PARI program for A331524</a>
%e The first terms, alongside A006686(n), are:
%e n a(n) A006686(n)
%e -- ---- -----------------------
%e 1 1 2 = 1^8 + 1^8
%e 2 1 257 = 1^8 + 2^8
%e 3 1 65537 = 1^8 + 4^8
%e 4 5 2070241 = 5^8 + 6^8
%e 5 3 100006561 = 3^8 + 10^8
%e 6 7 435746497 = 7^8 + 12^8
%e 7 2 815730977 = 2^8 + 13^8
%e 8 8 832507937 = 8^8 + 13^8
%e 9 3 1475795617 = 3^8 + 14^8
%e 10 8 2579667841 = 8^8 + 15^8
%o (PARI) See Links section.
%Y See A331435 for similar sequences.
%Y Cf. A001016, A006686.
%K nonn
%O 1,4
%A _Rémy Sigrist_, Jan 19 2020