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A101681 Numbers k such that gcd (C(2k,k), 2k+1) > 1. 1
7, 16, 17, 19, 22, 25, 31, 34, 38, 42, 43, 45, 46, 47, 49, 52, 55, 58, 61, 64, 67, 70, 71, 72, 73, 76, 77, 79, 80, 82, 87, 88, 92, 93, 94, 97, 100, 102, 103, 104, 106, 107, 110, 112, 115, 117, 122, 123, 124, 127, 129, 130, 133, 136, 139, 142, 143, 145, 147, 148 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Positions where A056616 differs from A000984.

The set seems to have greater cardinality than its complement.

LINKS

Table of n, a(n) for n=1..60.

CROSSREFS

Cf. A000984, A056616.

Sequence in context: A258771 A063593 A070417 * A067776 A193688 A132348

Adjacent sequences:  A101678 A101679 A101680 * A101682 A101683 A101684

KEYWORD

nonn

AUTHOR

Ralf Stephan, Dec 11 2004

STATUS

approved

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Last modified October 20 15:44 EDT 2017. Contains 293626 sequences.