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A134192 a(0) = a(1) = 1. a(n) = Sum_{p|n} a(n-p), where the sum is over all distinct primes p that divide n. 0
1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 3, 1, 5, 1, 6, 8, 6, 1, 14, 1, 22, 20, 23, 1, 43, 22, 44, 43, 64, 1, 129, 1, 129, 152, 130, 193, 282, 1, 283, 326, 476, 1, 995, 1, 1147, 1471, 1148, 1, 2619, 995, 4090, 2749, 4416, 1, 7165, 5237, 8160, 7448, 8161, 1, 20846, 1, 20847, 29006 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,7

LINKS

Table of n, a(n) for n=0..63.

EXAMPLE

The distinct primes that divide 12 are 2 and 3. So a(12) = a(12-2) + a(12-3) = a(10) + a(9) = 3 + 2 = 5.

MATHEMATICA

a = {1, 1}; For[n = 2, n < 80, n++, s = 0; For[i = 1, i < Length[Divisors[n]] + 1, i++, If[PrimeQ[Divisors[n][[i]]], s = s + a[[n - Divisors[n][[i]] + 1]]]]; AppendTo[a, s]]; a (* Stefan Steinerberger, Aug 30 2008 *)

CROSSREFS

Sequence in context: A318717 A331887 A328220 * A309342 A284044 A126305

Adjacent sequences:  A134189 A134190 A134191 * A134193 A134194 A134195

KEYWORD

nonn

AUTHOR

Leroy Quet, Jan 13 2008

EXTENSIONS

More terms from Stefan Steinerberger, Aug 30 2008

STATUS

approved

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Last modified April 1 03:22 EDT 2020. Contains 333155 sequences. (Running on oeis4.)