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.

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A244463 Number of unlabeled rooted trees with n nodes such that the minimal outdegree of inner nodes equals 9.

Original entry on oeis.org

1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 2, 2, 2, 2, 2, 2, 4, 7, 12, 16, 21, 25, 30, 34, 39, 47, 61, 83, 117, 160, 215, 280, 356, 442, 549, 682, 864, 1112, 1458, 1919, 2533, 3313, 4298, 5521, 7057, 8995, 11497, 14751, 19042, 24687, 32102, 41731, 54172, 70112, 90535
Offset: 10

Views

Author

Joerg Arndt and Alois P. Heinz, Jun 29 2014

Keywords

Crossrefs

Column k=9 of A244454.
Cf. A244538.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, `if`(t in [0, k],
          1, 0), `if`(i<1 or t>n, 0, add(binomial(b((i-1)$2, k$2)+j-1, j)*
          b(n-i*j, i-1, max(0,t-j), k), j=0..n/i)))
        end:
    a:= n-> b(n-1$2, 9$2) -b(n-1$2, 10$2):
    seq(a(n), n=10..75);

A244464 Number of unlabeled rooted trees with n nodes such that the minimal outdegree of inner nodes equals 10.

Original entry on oeis.org

1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 7, 12, 16, 21, 25, 30, 34, 39, 43, 52, 65, 88, 121, 165, 219, 285, 360, 447, 544, 661, 805, 998, 1256, 1613, 2085, 2709, 3500, 4496, 5709, 7201, 9016, 11277, 14108, 17738, 22410, 28484, 36330
Offset: 11

Views

Author

Joerg Arndt and Alois P. Heinz, Jun 29 2014

Keywords

Crossrefs

Column k=10 of A244454.
Cf. A244539.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, `if`(t in [0, k],
          1, 0), `if`(i<1 or t>n, 0, add(binomial(b((i-1)$2, k$2)+j-1, j)*
          b(n-i*j, i-1, max(0,t-j), k), j=0..n/i)))
        end:
    a:= n-> b(n-1$2, 10$2) -b(n-1$2, 11$2):
    seq(a(n), n=11..80);
Previous Showing 11-12 of 12 results.