A080895 - cp's OEIS frontend

A080895 Expansion of the exponential series exp( x R(x) ) = exp((1 + x - sqrt(1 - 2 x - 3x^2))/(2(1 + x))), where R(x) is the ordinary generating series of the Riordan numbers A005043.

n	a(n)
0	1
1	1
2	1
3	7
4	49
5	541
6	7321
7	122011
8	2390977
9	54027289
10	1382140081
11	39493358191
12	1246693438321
13	43087256236597
14	1618203187947529
15	65621724413560771
16	2857736621103221761
17	133014764141210620081
18	6589916027200886776417

[1, 1, 1, 7, 49, 541, 7321, 122011, 2390977, 54027289, 1382140081, 39493358191, 1246693438321, 43087256236597, 1618203187947529, 65621724413560771, 2857736621103221761, 133014764141210620081, 6589916027200886776417]

cp's OEIS Frontend

A080895 Expansion of the exponential series exp( x R(x) ) = exp((1 + x - sqrt(1 - 2 x - 3x^2))/(2(1 + x))), where R(x) is the ordinary generating series of the Riordan numbers A005043.

Table of values

List of values