A116669 Triangle, rows tend to A001787, number of edges in n-dimensional hypercubes.

1, 1, 1, 1, 4, 1, 1, 4, 7, 1, 1, 4, 12, 10, 1, 1, 4, 12, 25, 13, 1, 1, 4, 12, 32, 43, 16, 1, 1, 4, 12, 32, 71, 66, 19, 1, 1, 4, 12, 32, 80, 136, 94, 22, 1

Offset

1,5

Comments

Rows tend to A001787: 1, 4, 12, 32, 80, 192, 448...(number of edges in n-dimensional hypercubes). First difference terms of the triangle columns become rows of the triangle A116666.

Links

Table of n, a(n) for n=1..45.

Formula

Construct an array formed by taking binomial transforms of (1,0,0,0...); (1,3,0,0,0...); (1,3,5,0,0,0). Antidiagonals of the array become rows of the triangle.

Example

First few rows of the array are:
1 1 1 1 1...
1 4 7 10 13...
1 4 12 25 43...
1 4 12 32 71...
...
By taking antidiagonals, first few rows of the triangle are:
1;
1, 1;
1, 4, 1;
1, 4, 7, 1;
1, 4, 12, 10, 1;
1, 4, 12, 25, 13, 1;
...

Crossrefs

Cf. A001787, A116666, A116668.

Sequence in context: A285788 A293434 A091570 * A016523 A026998 A326812

Adjacent sequences: A116666 A116667 A116668 * A116670 A116671 A116672

Keyword

nonn,tabl

Author

Gary W. Adamson, Feb 22 2006

Status

approved