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A130499 a(1)=1. a(n) = number of earlier terms of the sequence which are coprime to (the sum of positive integers which are <=n and missing from first (n-1) terms of sequence). 2
1, 1, 2, 3, 3, 3, 5, 6, 6, 6, 10, 5, 7, 13, 14, 6, 9, 17, 18, 5, 7, 13, 13, 7, 13, 13, 8, 27, 24, 25, 30, 19, 30, 15, 29, 17, 36, 22, 19, 15, 40, 41, 16, 39, 38, 24, 28, 28, 48, 39, 29, 30, 50, 34, 30, 30, 55, 31, 25, 25, 30, 61, 44, 29, 27, 37, 38, 36, 65, 28, 63, 38, 45, 28, 54 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Diana Mecum, Table of n, a(n) for n=1,...,569

EXAMPLE

The positive integers which are <= 9 and are missing from the first 8 terms of the sequence are 4,7,8,9. The sum of these integers is 28, so a(9) is the number of earlier terms which are coprime to 28. Therefore a(9) = 6.

CROSSREFS

Cf. A130498.

Sequence in context: A141418 A287771 A335107 * A020910 A029065 A263253

Adjacent sequences:  A130496 A130497 A130498 * A130500 A130501 A130502

KEYWORD

nonn

AUTHOR

Leroy Quet, May 31 2007

EXTENSIONS

Added terms a(12) - a(569) Diana L. Mecum, Jan 01 2009

STATUS

approved

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Last modified May 9 07:36 EDT 2021. Contains 343692 sequences. (Running on oeis4.)