The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A184941 Irregular triangle C(n,g) counting the connected 4-regular simple graphs on n vertices with girth at least g. 7
 1, 1, 2, 6, 1, 16, 0, 59, 2, 265, 2, 1544, 12, 10778, 31, 88168, 220, 805491, 1606, 8037418, 16828, 86221634, 193900, 985870522, 2452818, 11946487647, 32670330, 1, 152808063181, 456028474, 2, 2056692014474, 6636066099, 8, 28566273166527, 100135577747, 131 (list; graph; refs; listen; history; text; internal format)
 OFFSET 5,3 COMMENTS The first column is for girth at least 3. The row length sequence starts: 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4. The row length is incremented to g-2 when n reaches A037233(g). LINKS EXAMPLE 1; 1; 2; 6, 1; 16, 0; 59, 2; 265, 2; 1544, 12; 10778, 31; 88168, 220; 805491, 1606; 8037418, 16828; 86221634, 193900; 985870522, 2452818; 11946487647, 32670330, 1; 152808063181, 456028474, 2; 2056692014474, 6636066099, 8; 28566273166527, 100135577747, 131; CROSSREFS Connected 4-regular simple graphs with girth at least g: this sequence (triangle); chosen g: A006820 (g=3), A033886 (g=4), A058343 (g=5), A058348 (g=6). Connected 4-regular simple graphs with girth exactly g: A184940 (triangle); chosen g: A184943 (g=3), A184944 (g=4), A184945 (g=5), A184946 (g=6). Triangular arrays C(n,g) counting connected simple k-regular graphs on n vertices with girth at least g: A185131 (k=3), this sequence (k=4), A184951 (k=5), A184961 (k=6), A184971 (k=7), A184981 (k=8). Sequence in context: A109530 A264789 A111519 * A185340 A280568 A280836 Adjacent sequences:  A184938 A184939 A184940 * A184942 A184943 A184944 KEYWORD nonn,hard,tabf AUTHOR Jason Kimberley, Jan 10 2012 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 6 17:20 EDT 2020. Contains 334829 sequences. (Running on oeis4.)