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 A130632 Number of natural numbers between d(n) and d(n+1), where d(n) denotes the number of divisors of n. 1
 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 3, 3, 1, 0, 0, 2, 3, 3, 3, 1, 0, 1, 5, 4, 0, 0, 1, 3, 5, 5, 3, 1, 0, 0, 4, 6, 1, 0, 3, 5, 5, 5, 3, 0, 1, 1, 7, 6, 2, 1, 1, 3, 5, 3, 3, 3, 0, 1, 9, 9, 1, 1, 0, 2, 3, 5, 3, 1, 3, 5, 9, 9, 1, 1, 0, 1, 3, 5, 7, 4, 0, 1, 9, 7, 0, 0, 3, 5, 9, 7, 1, 1, 0, 0, 7, 9, 3, 0, 2, 6, 5, 5, 5, 0, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,11 LINKS Antti Karttunen, Table of n, a(n) for n = 1..20000 FORMULA a(n) = max(0, |A051950(n+1)| - 1). - R. J. Mathar, Jun 28 2010 MAPLE A051950 := proc(n) if n = 0 then 1; else numtheory[tau](n+1)-numtheory[tau](n) ; end if; end proc: A130632 := proc(n) local g ; g := abs(A051950(n)) ; max(0, g-1) ; end proc: seq(A130632(n), n=1..80) ; # R. J. Mathar, Jun 28 2010 PROG (PARI) a(n) = max(0, abs(numdiv(n+1)-numdiv(n))-1); \\ Michel Marcus, Aug 24 2015 CROSSREFS Cf. A000005, A051950. Sequence in context: A261477 A205826 A131193 * A229158 A290454 A281066 Adjacent sequences:  A130629 A130630 A130631 * A130633 A130634 A130635 KEYWORD nonn AUTHOR Giovanni Teofilatto, Aug 11 2007 EXTENSIONS More terms from R. J. Mathar, Jun 28 2010 Extended up to a(105) by Antti Karttunen, Oct 07 2017 STATUS approved

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Last modified January 17 16:45 EST 2021. Contains 340247 sequences. (Running on oeis4.)