login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A050532 Number of multigraphs with loops on 4 nodes with n edges. 3
1, 2, 7, 20, 53, 125, 287, 606, 1226, 2358, 4356, 7740, 13327, 22239, 36151, 57336, 88962, 135249, 201912, 296324, 428211, 609935, 857327, 1190216, 1633551, 2218011, 2981607, 3970548, 5241120, 6861024, 8911782, 11490282, 14711976 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

G.f.: (4*x^11+4*x^10+11*x^9+15*x^8+9*x^7+12*x^6+6*x^5+6*x^4+3*x^3+2*x^2-x+1)/((x^4-1)^2*(x^3-1)^3*(x^2-1)^2*(x-1)^3).

CROSSREFS

Cf. A002620.

Sequence in context: A134311 A066373 A096005 * A050513 A128183 A027418

Adjacent sequences:  A050529 A050530 A050531 * A050533 A050534 A050535

KEYWORD

easy,nonn

AUTHOR

Vladeta Jovovic (vladeta(AT)eunet.rs), Dec 29 1999

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 09:17 EST 2012. Contains 206009 sequences.