A194950 Column 0 of triangle A194949 = shifted row sums of triangle A194949.

1, 1, 2, 6, 20, 72, 260, 996, 3772, 14852, 58204, 234236, 934180, 3825428, 15493292, 64009212, 263052756, 1096235844, 4537607788, 19075092364, 79566093524, 336047432420, 1412387294716, 5993817852300, 25302001904628, 107911381154004, 457634804571804

Offset

0,3

Links

Table of n, a(n) for n=0..26.

Prog

(PARI) {a(n)=local(M=matrix(n+1, n+1, r, c, if(r>=c, 1))); for(i=1, n, M=matrix(n+1, n+1, r, c, if(r>=c, if(c==1, if(r==1, 1, sum(j=1, r-1, (M*M~)[r-j, j])), (M*M~)[r-c+1, c])))); M[n+1, 1]}

Crossrefs

Cf. A194949, A194951.

Sequence in context: A370446 A150128 A148480 * A150129 A360267 A360291

Adjacent sequences: A194947 A194948 A194949 * A194951 A194952 A194953

Keyword

nonn

Author

Paul D. Hanna, Sep 05 2011

Status

approved