OFFSET
1,3
COMMENTS
EXAMPLE
Taking difference rows of A117189, we get:
1, 2, 5, 14, 40, 114, ...
1, 3, 9, 26, 74, ...
2, 6, 17, 48, ...
4, 11, 31, ...
7, 20, ...
13, ...
Reorient into the triangle:
1;
1, 2;
2, 3, 5;
4, 6, 9, 14;
7, 11, 17, 26, 40;
...
PROG
(PARI) lista(nn) = my(va = Vec(-(x-1)^2/(-1+4*x-4*x^2+2*x^3) + O(x^(nn))), v = vector(nn)); v[1] = va; for (n=2, nn, v[n] = vector(nn-n+1, k, v[n-1][k+1] - v[n-1][k]); ); my(list = List()); for (n=1, nn, my(i = n, j = 1); for (k=1, n, listput(list, v[i][j]); i--; j++; ); ); Vec(list); \\ Michel Marcus, Aug 10 2023
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Mar 05 2006
EXTENSIONS
More terms from Michel Marcus, Aug 10 2023
STATUS
approved