login
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
OFFSET
1,3
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 A374022 A029065
KEYWORD
nonn
AUTHOR
Leroy Quet, May 31 2007
EXTENSIONS
Added terms a(12) - a(569) Diana L. Mecum, Jan 01 2009
STATUS
approved