This site is supported by donations to The OEIS Foundation.

 Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS". Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A095934 G.f.: (1-x)^2/(1-5*x+3*x^2). 2
 1, 3, 13, 56, 241, 1037, 4462, 19199, 82609, 355448, 1529413, 6580721, 28315366, 121834667, 524227237, 2255632184, 9705479209, 41760499493, 179686059838, 773148800711, 3326685824041, 14313982718072, 61589856118237, 265007332436969, 1140267093830134 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS a(n) is the number of generalized compositions of n when there are i+2 different types of i, (i=1,2,...). [From Milan Janjic, Sep 24 2010] REFERENCES P. J. Cameron, Some sequences of integers, Discrete Math., 75 (1989), 89-102; also in "Graph Theory and Combinatorics 1988", ed. B. Bollobas, Annals of Discrete Math., 43 (1989), 89-102. LINKS Index entries for linear recurrences with constant coefficients, signature (5,-3). FORMULA a(n+2) = 5a(n+1) - 3a(n) (n >= 1); a(0) = 1, a(1) = 3, a(2) = 13. PROG (PARI) a(n)=polcoeff((1-x)^2/(1-5*x+3*x^2)+x*O(x^n), n) CROSSREFS Cf. A003480, A010903, A010920; equals A095939 + A095940. Sequence in context: A234645 A010920 A010903 * A151220 A151221 A020515 Adjacent sequences:  A095931 A095932 A095933 * A095935 A095936 A095937 KEYWORD nonn,easy AUTHOR N. J. A. Sloane, Jul 13 2004 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.