

A175051


a(n) is the number of divisors of A175050(n).


3



1, 4, 4, 9, 9, 4, 8, 9, 16, 9, 9, 4, 9, 9, 9, 27, 16, 9, 9, 9, 25, 4, 9, 9, 27, 9, 8, 4, 27, 9, 16, 9, 9, 9, 16, 9, 9, 27, 9, 27, 4, 9, 9, 27, 27, 9, 9, 4, 9, 9, 9, 36, 9, 9, 9, 9, 16, 25, 27, 16, 27, 9, 27, 4, 9, 27, 27, 9, 9, 9, 9, 9, 9, 27, 16, 9, 9, 27, 9, 9, 9, 9, 9, 27, 9, 4, 9, 9, 9, 27, 64, 27
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OFFSET

1,2


COMMENTS

All terms of this sequence (as well as all of those of sequence A175050) are perfect powers. (I.e., the terms of both of these sequences are terms of sequence A001597.)


LINKS



MATHEMATICA

Block[{nn = 10^5, s}, s = Union@ Flatten@ Table[n^e, {e, Prime@ Range@ PrimePi@ Log2@ nn}, {n, nn^(1/e)}]; Select[DivisorSigma[0, s], MemberQ[s, #] &]] (* Michael De Vlieger, Nov 24 2017, after T. D. Noe at A001597 *)


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



