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A062774 Inverse Moebius transform of PrimePi function. +0
1
0, 1, 2, 3, 3, 6, 4, 7, 6, 8, 5, 13, 6, 11, 11, 13, 7, 17, 8, 18, 14, 14, 9, 26, 12, 16, 15, 22, 10, 29, 11, 24, 18, 19, 18, 35, 12, 21, 20, 34, 13, 37, 14, 30, 29, 24, 15, 47, 19, 32, 24, 33, 16, 42, 24, 42, 26, 27, 17, 61, 18, 30, 36, 42, 27, 48, 19, 40, 30, 48, 20, 68, 21, 34 (list; graph; listen)
OFFSET

1,3

LINKS

Harry J. Smith, Table of n, a(n) for n=1,...,1000

FORMULA

a(n)=Sum {Pi(d)}, d divides n.

EXAMPLE

n = 12: divisors = D(12) = {1,2,3,4,6,12}, Pi[D(12)] = {0,1,2,2,3,5} of which the sum is 0+1+2+2+3+5 = 13 so a(12) = 13; a(p[n]) = 0+n = n, for n-th prime p[n].

PROGRAM

(PARI) { for (n=1, 1000, d=divisors(n); write("b062774.txt", n, " ", sum(k=1, length(d), primepi(d[k]))) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 10 2009]

CROSSREFS

Cf. A007444, A007445.

Sequence in context: A021432 A141729 A049990 this_sequence A045892 A160791 A115973

Adjacent sequences: A062771 A062772 A062773 this_sequence A062775 A062776 A062777

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Jul 18 2001

EXTENSIONS

OFFSET changed from 0,3 to 1,3 by Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 10 2009

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Last modified November 29 12:46 EST 2009. Contains 167659 sequences.


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