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 A151948 a(n) = tau(sigma(phi(n))). 1
 1, 1, 2, 2, 2, 2, 6, 2, 6, 2, 6, 2, 6, 6, 4, 4, 2, 6, 4, 4, 6, 6, 9, 4, 8, 6, 4, 6, 8, 4, 12, 2, 8, 2, 12, 6, 4, 4, 12, 2, 12, 6, 12, 8, 12, 9, 12, 2, 12, 8, 6, 12, 6, 4, 12, 12, 4, 8, 12, 2, 16, 12, 4, 6, 6, 8, 15, 6, 12, 12, 15, 12, 8, 4, 12, 4, 16, 12, 16 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Antti Karttunen, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A000005(A000203(A000010(n))) = A000005(A062402(n)) = A062068(A000010(n)). PROG (PARI) A151948(n) = numdiv(sigma(eulerphi(n))); \\ Antti Karttunen, Aug 22 2017 CROSSREFS Cf. A000005, A000010, A000203, A062068, A062402, A163375. Sequence in context: A164126 A261902 A163368 * A080400 A119462 A293221 Adjacent sequences:  A151945 A151946 A151947 * A151949 A151950 A151951 KEYWORD nonn AUTHOR Jaroslav Krizek, Jul 20 2009 STATUS approved

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Last modified December 15 13:27 EST 2018. Contains 318149 sequences. (Running on oeis4.)