

A126698


a(0)=1. For n>=1, a(n) = a(n1) + (largest divisor of n which does not occur among the earlier terms of the sequence); or a(n) = a(n1) if every divisor of n occurs among the earlier terms of the sequence.


0



1, 1, 3, 3, 7, 12, 18, 18, 26, 35, 45, 56, 62, 75, 89, 104, 120, 137, 146, 165, 185, 206, 228, 251, 275, 300, 313, 340, 368, 397, 427, 458, 490, 523, 557, 562, 598, 635, 673, 712, 752, 793, 835, 878, 922, 937, 983, 1030, 1078, 1127, 1177, 1228, 1280, 1333
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OFFSET

0,3


LINKS

Table of n, a(n) for n=0..53.


MATHEMATICA

f[l_List] := Block[{c}, c = Complement[Divisors[Length[l]], l]; Append[l, l[[ 1]] + If[c == {}, 0, Max @@ c]]]; Nest[f, {1}, 55] (* Ray Chandler, Feb 19 2007 *)


CROSSREFS

Sequence in context: A006661 A343752 A068626 * A219211 A088859 A177942
Adjacent sequences: A126695 A126696 A126697 * A126699 A126700 A126701


KEYWORD

nonn


AUTHOR

Leroy Quet, Feb 15 2007


EXTENSIONS

Extended by Ray Chandler, Feb 19 2007


STATUS

approved



