A168591 a(n) = sum of the n-th power of the trinomial coefficients in row n of triangle A027907.

1, 3, 19, 831, 281907, 764206503, 16955359883149, 3120135986465328015, 4819828380706011142058787, 63004580363300194268932114354503, 7017256966823394610075464951176481843849

Offset

0,2

Links

Table of n, a(n) for n=0..10.

Formula

Ignoring initial term, equals the logarithmic derivative of A168590.

Prog

(PARI) a(n)=sum(k=0, 2*n, polcoeff((1+x+x^2)^n, k)^n)

Crossrefs

Cf. A168590, A027907.

Sequence in context: A107706 A373626 A330040 * A290119 A319190 A350121

Adjacent sequences: A168588 A168589 A168590 * A168592 A168593 A168594

Keyword

nonn

Author

Paul D. Hanna, Dec 01 2009

Status

approved