cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A261642 Triangle, read by rows, where T(n,k) = (k^2 + k)^(n-k) for k=1..n and n>=1.

Original entry on oeis.org

1, 2, 1, 4, 6, 1, 8, 36, 12, 1, 16, 216, 144, 20, 1, 32, 1296, 1728, 400, 30, 1, 64, 7776, 20736, 8000, 900, 42, 1, 128, 46656, 248832, 160000, 27000, 1764, 56, 1, 256, 279936, 2985984, 3200000, 810000, 74088, 3136, 72, 1, 512, 1679616, 35831808, 64000000, 24300000, 3111696, 175616, 5184, 90, 1
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2015

Keywords

Comments

Matrix inverse of triangle P with element P(n,k) = (-1)^(n-k) * (k^2 + k)^(n-k) / (n-k)! forms triangle A103244.

Examples

			This triangle begins:
1;
2, 1;
4, 6, 1;
8, 36, 12, 1;
16, 216, 144, 20, 1;
32, 1296, 1728, 400, 30, 1;
64, 7776, 20736, 8000, 900, 42, 1;
128, 46656, 248832, 160000, 27000, 1764, 56, 1;
256, 279936, 2985984, 3200000, 810000, 74088, 3136, 72, 1;
512, 1679616, 35831808, 64000000, 24300000, 3111696, 175616, 5184, 90, 1;
1024, 10077696, 429981696, 1280000000, 729000000, 130691232, 9834496, 373248, 8100, 110, 1; ...
		

Crossrefs

Cf. A103244, A261643 (row sums).

Programs

  • PARI
    {T(n, k) = (k^2 + k)^(n-k)}
    for(n=1, 10, for(k=1, n, print1(T(n, k), ", ")); print(""))