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A072992 Numbers n such that sigma(n) does not divide C(2n,n). 0
10, 18, 21, 22, 27, 30, 33, 34, 35, 40, 42, 45, 52, 55, 56, 57, 58, 65, 66, 69, 70, 75, 77, 81, 82, 84, 85, 88, 90, 93, 94, 98, 100, 102, 105, 106, 108, 110, 115, 118, 119, 120, 121, 129, 132, 133, 135, 136, 138, 140, 141, 148, 152, 154, 155, 156, 161, 162, 164 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

FORMULA

It seems that a(n) is asymptotic to C*n with C=2.8...

CROSSREFS

Sequence in context: A043750 A043758 A043767 * A055481 A165250 A125689

Adjacent sequences:  A072989 A072990 A072991 * A072993 A072994 A072995

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Aug 21 2002

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Last modified February 17 02:31 EST 2012. Contains 205978 sequences.