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 A171937 Forward van Eck transform of A000005. 4
 0, 1, 2, 5, 2, 2, 4, 2, 16, 4, 2, 6, 4, 1, 6, 65, 2, 2, 4, 8, 1, 4, 6, 6, 24, 1, 6, 4, 2, 10, 6, 12, 1, 1, 3, 64, 4, 1, 7, 2, 2, 12, 4, 1, 5, 5, 6, 32, 72, 2, 4, 11, 6, 2, 2, 10, 1, 4, 2, 12, 6, 3, 5, 665, 4, 4, 4, 7, 5, 8, 2, 12, 6, 3, 1, 16, 5, 10, 4, 32, 544, 3, 6, 6, 1, 1, 4, 14, 8, 6, 2, 6, 1, 1, 11 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Least positive k such that d(n) = d(n+k), or 0 if no such k exists (d = A000005). - Altug Alkan, Jul 29 2016 LINKS Michael De Vlieger, Table of n, a(n) for n = 1..10001 N. J. A. Sloane, Transforms FORMULA a(n) = A079427(n) - n. - Ridouane Oudra, Sep 14 2021 MATHEMATICA {0}~Join~Array[Block[{k = 1}, While[DivisorSigma[0, #] != DivisorSigma[0, # + k], k++]; k] &, 94, 2] (* Michael De Vlieger, Aug 19 2021 *) PROG (PARI) a(n) = if (n==1, 0, my(m=1, nd=numdiv(n)); while(numdiv(n+m) != nd, m++); m); \\ Michel Marcus, Sep 14 2021 CROSSREFS Cf. A000005, A171936. Cf. A079427. Sequence in context: A286664 A306541 A242242 * A065291 A065267 A273990 Adjacent sequences: A171934 A171935 A171936 * A171938 A171939 A171940 KEYWORD nonn AUTHOR N. J. A. Sloane, Oct 24 2010 STATUS approved

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Last modified September 23 16:20 EDT 2023. Contains 365554 sequences. (Running on oeis4.)