cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A115190 Fourth diagonal (M=4) of triangle A115154 (called Y(3,1)).

Original entry on oeis.org

1, 121, 1762, 20989, 235543, 2588641, 28259704, 308277688, 3369314986, 36937817182, 406378312834, 4487124168115, 49722977591155, 552884158181785, 6167643983348920, 69012419067802540, 774413615153430670
Offset: 0

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Author

Wolfdieter Lang, Feb 23 2006

Keywords

Examples

			a(0)= 1 = 190 - 9*(25-4); a(2) = 1762 = 14506 - 9*(1606-190).
		

Formula

a(n)= A115154(n+3,n+1), n>=0.
Recurrence: a(n)= b(n) - 9*(b(n-1)-b(n-2)), with b(n):=A064063(n+4), n>=0.
G.f.: ((-3+18*x+2*x^3) + 3*(1-9*x+9*x^2)*c(3*x))/((2+x)*x^3), with the o.g.f. c(x) of A000108 (Catalan).