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 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 (list; graph; refs; listen; history; text; internal format)
 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 Michael De Vlieger, Table of n, a(n) for n = 1..10000 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 Cf. A001597, A175050. Sequence in context: A362294 A198497 A231980 * A011364 A016713 A343620 Adjacent sequences: A175048 A175049 A175050 * A175052 A175053 A175054 KEYWORD nonn AUTHOR Leroy Quet, Dec 08 2009 EXTENSIONS Extended by Ray Chandler, Dec 10 2009 STATUS approved

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Last modified September 8 14:54 EDT 2024. Contains 375753 sequences. (Running on oeis4.)