A155108 Primes k such that the k-th composite is even.

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

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 * A356856 A222565 A113188

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