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A126090 a(1)=1. a(n) = the number of terms among {a(1),a(2),...a(n-1)} which are coprime to exactly one distinct prime dividing n. 1
1, 1, 2, 2, 4, 3, 6, 3, 5, 5, 10, 6, 12, 7, 8, 5, 16, 8, 18, 13, 7, 11, 22, 10, 17, 14, 18, 16, 28, 9, 30, 11, 12, 20, 11, 16, 36, 22, 12, 23, 40, 14, 42, 28, 19, 29, 46, 22, 39, 28, 15, 33, 52, 28, 16, 29, 17, 36, 58, 20, 60, 38, 25, 22, 15, 23, 66, 43, 23, 20, 70, 37, 72, 45 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Diana Mecum, Table of n, a(n) for n = 1..500

EXAMPLE

There are 6 terms among the first 11 terms of the sequence which are each coprime to exactly one distinct prime dividing 12 (a(3)=2, a(4)=2, a(5)=4, a(6)=3, a(8)=3 and a(11)=10). So a(12) = 6.

CROSSREFS

Cf. A126080.

Sequence in context: A087656 A122811 A089173 * A058266 A138664 A140357

Adjacent sequences:  A126087 A126088 A126089 * A126091 A126092 A126093

KEYWORD

nonn

AUTHOR

Leroy Quet, Mar 03 2007

EXTENSIONS

More terms from Diana L. Mecum, Jun 23 2007

STATUS

approved

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Last modified November 22 05:52 EST 2018. Contains 317453 sequences. (Running on oeis4.)