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A137809 a(0) = a(1) = 1. a(n) = a(n-1) + a(n-b(n)), where b(n) is largest prime dividing n. +0
2
1, 1, 2, 3, 5, 6, 9, 10, 19, 28, 34, 35, 63, 64, 74, 108, 182, 183, 291, 292, 400, 474, 509, 510, 984, 1384, 1448, 2432, 2906, 2907, 4291, 4292, 8583, 9092, 9275, 12181, 21273, 21274, 21566, 23014, 35195, 35196, 47377, 47378, 56470, 91665, 92175, 92176 (list; graph; listen)
OFFSET

0,3

LINKS

James A. Sellers (sellersj(AT)math.psu.edu), Feb 18 2008, Table of n, a(n) for n = 0..100

Leroy Quet, Home Page (listed in lieu of email address)

MAPLE

with(numtheory): a:=proc(n) option remember: if n = 0 or n = 1 then RETURN(1) fi: a(n-1) + a(n-ifactors(n)[2][nops(ifactors(n)[2])][1]): end: for i from 0 to 100 do printf(`%d, `, a(i)) od: - James A. Sellers (sellersj(AT)math.psu.edu), Feb 18 2008

MATHEMATICA

a = {1, 1}; Do[AppendTo[a, a[[ -1]] + a[[n - FactorInteger[n][[ -1, 1]] + 1]]], {n, 2, 70}]; a - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Feb 14 2008

CROSSREFS

Cf. A137808, A006530.

Sequence in context: A018659 A018365 A018278 this_sequence A014838 A026459 A026461

Adjacent sequences: A137806 A137807 A137808 this_sequence A137810 A137811 A137812

KEYWORD

nonn

AUTHOR

Leroy Quet Feb 11 2008

EXTENSIONS

More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Feb 14 2008

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


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