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 A225675 Numbers n such that triangular(n) is representable as p*w, where p is a prime number and w is a prime power (A025475). 0

%I

%S 2,7,9,16,17,18,25,26,31,53,81,97,121,127,162,241,250,256,337,361,486,

%T 577,625,841,1249,1458,2186,2401,2662,3361,3481,3697,3721,4373,4801,

%U 5041,6241,6961,8191,10201,10657,13121,14641,17161,19321,23761,25537,28561,31249,32257

%N Numbers n such that triangular(n) is representable as p*w, where p is a prime number and w is a prime power (A025475).

%C Corresponding triangular numbers are in A225674.

%C The subsequence of even terms begins: 2, 16, 18, 26, 162, 250, 256, 486, 1458, 2186, 2662, 39366, 48778, 65536, 410758, 715822, 1594322, 2450086, 6615898, 12872686, 13935742, 15290746, 23394166, 38930218, 41022298, 86093442, ...

%Y Cf. A000040, A000217, A025475, A225674.

%K nonn

%O 1,1

%A _Alex Ratushnyak_, May 12 2013

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Last modified May 13 12:16 EDT 2021. Contains 343839 sequences. (Running on oeis4.)