A185016 Characteristic function of 6.

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

Offset

0,1

Comments

Number of connected 2-regular (simple) graphs with girth exactly 6.

The Euler transformation of this sequence is A079979.

Links

Table of n, a(n) for n=0..85.

Index entries for linear recurrences with constant coefficients, signature (1).

Formula

a(n) = A185116(n) - A185117(n).

Mathematica

PadRight[{0, 0, 0, 0, 0, 0, 1}, 100] (* Paolo Xausa, May 06 2026 *)

Prog

(Python)
def A185016(n): return int(n==6) # Chai Wah Wu, Feb 04 2022

Crossrefs

Characteristic function of g: A000007 (g=0), A063524 (g=1), A185012 (g=2), A185013 (g=3), A185014 (g=4), A185015 (g=5), this sequence (g=6), A185017 (g=7).

Sequence in context: A011710 A135500 A023972 * A103674 A358842 A358758

Adjacent sequences: A185013 A185014 A185015 * A185017 A185018 A185019

Keyword

nonn,easy

Author

Jason Kimberley, Sep 30 2011

Status

approved