A101874 Number of Abelian groups of order 4n+3.

1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 2, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 2, 1, 1, 3, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1

Offset: 0

Author

N. J. A. Sloane, Jan 28 2005

Keywords

• nonn
• easy

Crossrefs

Bisection of A101871.

Cf. A101873, A101876.

Programs

Mathematica

a[n_] := FiniteAbelianGroupCount[4*n + 3]; Array[a, 100, 0] (* Amiram Eldar, Sep 23 2023 *)

Extensions

More terms from Joshua Zucker, May 10 2006