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A155108 Primes k such that the k-th composite is even. 2
2, 3, 5, 7, 11, 13, 19, 29, 31, 37, 41, 43, 47, 59, 67, 71, 79, 83, 89, 101, 103, 107, 109, 113, 127, 137, 139, 149, 151, 157, 163, 179, 181, 197, 199, 211, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 293, 307, 311, 331, 337, 347, 349, 353, 359, 373, 389 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Muniru A Asiru, Table of n, a(n) for n = 1..20000

EXAMPLE

2 is a term because composite(2) = 6 (even);

3 is a term because composite(3) = 8 (even);

5 is a term because composite(5) = 10 (even);

7 is a term because composite(7) = 14 (even);

11 is a term because composite(11) = 20 (even).

PROG

(GAP) A:=Filtered([2..500], n->not IsPrime(n));;

a:=Filtered(Filtered([1..Length(A)], IsPrime), i->IsEvenInt(A[i])); # Muniru A Asiru, Feb 10 2019

CROSSREFS

Cf. A000040, A002808.

Sequence in context: A227202 A237827 A114111 * A222565 A113188 A242738

Adjacent sequences:  A155105 A155106 A155107 * A155109 A155110 A155111

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jan 20 2009

EXTENSIONS

Corrected (105 replaced by 107, 239 and 263 inserted) by R. J. Mathar, May 10 2010

STATUS

approved

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Last modified July 18 11:30 EDT 2019. Contains 325138 sequences. (Running on oeis4.)