A072978 Numbers of the form m*2^Omega(m), where m>1 is odd and Omega(m)=A001222(m), the number of prime factors of m.

1, 6, 10, 14, 22, 26, 34, 36, 38, 46, 58, 60, 62, 74, 82, 84, 86, 94, 100, 106, 118, 122, 132, 134, 140, 142, 146, 156, 158, 166, 178, 194, 196, 202, 204, 206, 214, 216, 218, 220, 226, 228, 254, 260, 262, 274, 276, 278, 298, 302, 308, 314, 326, 334, 340, 346

Offset

1,2

Comments

(number of odd prime factors)=(number of even prime factors).

A007814(a(n)) = A087436(a(n)); A000400, A011557, A001023, A001024, A009965, A009966 and A009975 are subsequences. - Reinhard Zumkeller, Jan 06 2008

Subsequence of A028260. - Reinhard Zumkeller, Sep 20 2008

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Mathematica

Join[{1}, Select[Range[2, 500, 2], First[#] == Total[Rest[#]] & [FactorInteger[#][[All, 2]]] &]] (* Paolo Xausa, Feb 19 2025 *)

Crossrefs

Cf. A001222, A007814, A087436.

Cf. A000400, A011557, A001023, A001024, A009965, A009966, A009975, A028260.

Sequence in context: A315234 A315235 A080784 * A381642 A369966 A055163

Adjacent sequences: A072975 A072976 A072977 * A072979 A072980 A072981

Keyword

nonn,nice

Author

Reinhard Zumkeller, Aug 20 2002

Status

approved