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A089646 a(n) = Sum(a(floor(n/p)): p prime and p<=n); a(1) = 1. 0
1, 1, 2, 2, 3, 4, 5, 5, 6, 7, 8, 9, 10, 11, 13, 13, 14, 16, 17, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 32, 33, 33, 35, 36, 38, 41, 42, 43, 45, 46, 47, 51, 52, 53, 56, 57, 58, 59, 60, 62, 64, 65, 66, 69, 71, 72, 74, 75, 76, 82, 83, 84, 87, 87, 89, 93, 94, 95, 97, 101, 102, 106 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

EXAMPLE

a(10) = a([10/2])+a([10/3])+a([10/5])+a([10/7]) =

a(5)+a(3)+a(2)+a(1) = (a([5/2])+a([5/3])+a([5/5])) + (a([3/2])+a([3/3])) +

a([2/2]) + a(1) = (a(2)+a(1)+a(1)) + (a(1)+a(1)) + a(1) + a(1) = a([2/2]) +

6*a(1) = a(1) + 6*1 = 7.

CROSSREFS

Cf. A022825.

Sequence in context: A105566 A064317 A127037 * A011884 A029070 A112341

Adjacent sequences:  A089643 A089644 A089645 * A089647 A089648 A089649

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jan 02 2004

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Last modified February 17 06:27 EST 2012. Contains 205998 sequences.