A210345 The number of degree sequences of simple graphs with n vertices with all even degrees.

1, 1, 2, 3, 7, 14, 36, 74, 201, 425, 1178, 2515, 7063, 15209, 43088, 93382, 266236, 579950, 1661548, 3634062, 10451798, 22935259, 66170288, 145601216, 421164456, 928875440, 2692737120, 5950570725, 17282501978, 38257352346, 111292168834, 246730727752, 718763328317, 1595578916923, 4653944394630

Offset

1,3

Comments

a(2n) = A210346(n). For even n, the complementary sequence has all odd degrees.

Links

Table of n, a(n) for n=1..35.

Example

For n=3, there are only two degree sequences with all even terms are possible: {0,0,0} and {2,2,2}. Thus, a(3)=2.

Crossrefs

Cf. A210346, A049339

Sequence in context: A113822 A036250 A191491 * A006660 A306844 A213906

Adjacent sequences: A210342 A210343 A210344 * A210346 A210347 A210348

Keyword

nonn

Author

Tanya Khovanova and Dai Yang, Mar 20 2012

Extensions

a(13)-a(35) from Robert Gerbicz, Apr 08 2012

Status

approved