A106138 Semiprimes (mod 2).

0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1

Offset

1,1

Links

Table of n, a(n) for n=1..105.

Formula

a(n) = A001358(n) mod 2.

Mathematica

Mod[Select[Range[ 327], PrimeOmega[#]==2&], 2] (* James C. McMahon, Jan 31 2024 *)

Crossrefs

Cf. A001358.

Sequence in context: A343219 A189640 A289057 * A273129 A288936 A064990

Adjacent sequences: A106135 A106136 A106137 * A106139 A106140 A106141

Keyword

nonn

Author

Shyam Sunder Gupta, May 07 2005

Status

approved