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%I #12 Sep 17 2018 15:44:41
%S 15,31,47,63,79,95,111,127,143,159,175,191,207,223,239,240,255,271,
%T 287,303,319,335,351,367,383,399,415,431,447,463,479,495,496,511,527,
%U 543,559,575,591,607,623,639,655,671,687,703,719,735,751,752,767,783,799,815
%N Numbers of the form 16^i*(16*j + 15).
%C {-a(n)} gives all negative fourth powers modulo all powers of 2, that is, negative fourth powers over 2-adic integers.
%H Jianing Song, <a href="/A319282/b319282.txt">Table of n, a(n) for n = 1..9999</a> (all terms <= 150000)
%F a(n) = 15*n + O(log(n)).
%o (PARI) isA319282(n)= n\16^valuation(n, 16)%16==15
%Y A125169 is a proper subsequence.
%Y Perfect powers over 2-adic integers:
%Y Squares: positive: A234000; negative: A004215 (negated);
%Y Cubes: A191257;
%Y Fourth powers: positive: A319281; negative: this sequence (negated).
%K nonn
%O 1,1
%A _Jianing Song_, Sep 16 2018