This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A132612 Column 1 of triangle A132610. 5
 1, 1, 4, 39, 648, 15465, 483240, 18685905, 861282832, 46085893011, 2807152825020, 191731595897600, 14510053796849640, 1205013817282706730, 108941005329522201360, 10650027832902977866245, 1119401271751383414197280, 125879457463215695125460535 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Triangle T=A132610 is generated by even matrix powers of itself such that row n+1 of T = row n of T^(2n) with appended '1' for n>=0 with T(0,0)=1. LINKS FORMULA a(n) is divisible by n for n>0; a(n)/n = A132614(n). a(n) = [x^(n-1)] (1+x)^(n*(n+1)) / F(x) for n>0, where F(x) is the g.f. of A304192. PROG (PARI) {a(n)=local(A=vector(n+2), p); A[1]=1; for(j=1, n-1, p=n^2-(n-j)^2; A=Vec((Polrev(A)+x*O(x^p))/(1-x))); A=Vec((Polrev(A)+x*O(x^p))/(1-x)); A[p+1]} for(n=0, 25, print1(a(n), ", ")) (PARI) {a(n)=local(A=[1]); for(i=1, n, A=Vec(Ser(A)/(1-x)^(2*(#A)-1)); A=concat(A, A[#A])); A[#A]} for(n=0, 25, print1(a(n), ", ")) CROSSREFS Cf. A132610 (triangle); other columns: A132611, A132613; A132614. Cf. A304192. Sequence in context: A178920 A066399 A065760 * A129463 A299426 A188418 Adjacent sequences:  A132609 A132610 A132611 * A132613 A132614 A132615 KEYWORD nonn AUTHOR Paul D. Hanna, Aug 23 2007 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 October 15 23:54 EDT 2019. Contains 328038 sequences. (Running on oeis4.)