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A163127 a(1)=1. a(n) is the number of integers k, 1 <= k <= n-1, where gcd(a(k), n-k) >= 2. 1
1, 0, 0, 1, 2, 2, 3, 3, 3, 4, 4, 5, 5, 5, 5, 5, 6, 6, 7, 8, 8, 8, 8, 9, 9, 11, 11, 10, 9, 11, 10, 12, 14, 12, 13, 14, 14, 16, 14, 17, 16, 15, 18, 17, 18, 18, 20, 20, 21, 18, 20, 23, 23, 22, 22, 23, 24, 22, 24, 25, 28, 24, 29, 23, 28, 27, 28, 26, 29, 26, 30, 30, 31, 32, 33, 31, 32, 31 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

For the purpose of this sequence, gcd(m,0) is considered to be m.

LINKS

Table of n, a(n) for n=1..78.

CROSSREFS

Cf. A163126.

Sequence in context: A330393 A273263 A274533 * A077113 A143796 A245473

Adjacent sequences:  A163124 A163125 A163126 * A163128 A163129 A163130

KEYWORD

nonn

AUTHOR

Leroy Quet, Jul 21 2009

EXTENSIONS

More terms from Sean A. Irvine, Oct 20 2009

STATUS

approved

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Last modified January 22 10:13 EST 2022. Contains 350481 sequences. (Running on oeis4.)