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.

Showing 1-9 of 9 results.

A245747 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 2.

Original entry on oeis.org

1, 2, 5, 10, 21, 42, 87, 178, 371, 773, 1630, 3447, 7346, 15712, 33790, 72922, 158020, 343494, 749101, 1638102, 3591723, 7893801, 17387930, 38379199, 84875595, 188036829, 417284180, 927469844, 2064465340, 4601670624, 10270463564, 22950838754, 51346678940
Offset: 4

Views

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Keywords

Crossrefs

Column k=2 of A244523.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
          `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
           b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
        end:
    a:= n-> b(n-1$2, 2$2) -b(n-1$2, 1$2):
    seq(a(n), n=4..60);
  • Mathematica
    b[n_, i_, t_, k_] := b[n, i, t, k] = If[n == 0, 1, If[i<1, 0, Sum[Binomial[ b[i-1, i-1, k, k], j]*b[n-i*j, i-1, t - j, k], {j, 0, Min[t, n/i]}]]];
    a[n_] :=  b[n-1, n-1, 2, 2] - b[n-1, n-1, 1, 1];
    Table[a[n], {n, 4, 60}] (* Jean-François Alcover, Aug 28 2021, after Maple code *)

Formula

a(n) = A063895(n+1)-1.

A245748 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 3.

Original entry on oeis.org

1, 3, 9, 25, 66, 170, 431, 1076, 2665, 6560, 16067, 39219, 95476, 231970, 562736, 1363640, 3301586, 7988916, 19322585, 46722160, 112955614, 273063236, 660116215, 1595906490, 3858740567, 9331539319, 22570697689, 54605064084, 132137719127, 319841444030
Offset: 7

Views

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Keywords

Crossrefs

Column k=3 of A244523.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
          `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
           b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
        end:
    a:= n-> b(n-1$2, 3$2) -b(n-1$2, 2$2):
    seq(a(n), n=7..60);
  • Mathematica
    b[n_, i_, t_, k_] := b[n, i, t, k] = If[n == 0, 1, If[i<1, 0, Sum[Binomial[ b[i-1, i-1, k, k], j]*b[n - i*j, i-1, t - j, k], {j, 0, Min[t, n/i]}]]];
    a[n_] := b[n-1, n-1, 3, 3] - b[n-1, n-1, 2, 2];
    Table[a[n], {n, 7, 60}] (* Jean-François Alcover, Aug 28 2021, after Maple code *)

Formula

a(n) = A116379(n) - A063895(n+1).

A245749 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 4.

Original entry on oeis.org

2, 6, 21, 63, 185, 512, 1403, 3750, 9928, 25969, 67462, 174039, 446884, 1142457, 2911078, 7396049, 18746761, 47420345, 119746936, 301941284, 760387426, 1912814031, 4807298905, 12071798139, 30292240853, 75965728619, 190398931985, 476980247827, 1194401725174
Offset: 11

Views

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Keywords

Crossrefs

Column k=4 of A244523.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
          `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
           b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
        end:
    a:= n-> b(n-1$2, 4$2) -b(n-1$2, 3$2):
    seq(a(n), n=11..60);
  • Mathematica
    b[n_, i_, t_, k_] := b[n, i, t, k] = If[n == 0, 1, If[i<1, 0, Sum[Binomial[ b[i-1, i-1, k, k], j]*b[n - i*j, i-1, t - j, k], {j, 0, Min[t, n/i]}]]];
    a[n_] :=  b[n-1, n-1, 4, 4] - b[n-1, n-1, 3, 3];
    Table[a[n], {n, 11, 60}] (* Jean-François Alcover, Aug 28 2021, after Maple code *)

Formula

a(n) = A116380(n) - A116379(n).

A245750 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 5.

Original entry on oeis.org

1, 7, 26, 91, 291, 885, 2588, 7373, 20555, 56413, 152812, 409696, 1089029, 2874506, 7542257, 19690939, 51188137, 132579401, 342294012, 881292334, 2263535926, 5801350565, 14840644204, 37901021924, 96650247055, 246137463494, 626087267035, 1590840361215
Offset: 15

Views

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Keywords

Crossrefs

Column k=5 of A244523.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
          `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
           b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
        end:
    a:= n-> b(n-1$2, 5$2) -b(n-1$2, 4$2):
    seq(a(n), n=15..60);
  • Mathematica
    b[n_, i_, t_, k_] := b[n, i, t, k] = If[n == 0, 1, If[i<1, 0, Sum[Binomial[ b[i-1, i-1, k, k], j]*b[n - i*j, i-1, t-j, k], {j, 0, Min[t, n/i]}]]];
    a[n_] := b[n-1, n-1, 5, 5] - b[n-1, n-1, 4, 4];
    Table[a[n], {n, 15, 60}] (* Jean-François Alcover, Aug 28 2021, after Maple code *)

A245751 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 6.

Original entry on oeis.org

3, 15, 70, 256, 884, 2840, 8788, 26238, 76511, 218462, 614003, 1702291, 4667792, 12678438, 34163511, 91424125, 243210889, 643652954, 1695711086, 4449529462, 11634279616, 30324707572, 78819222196, 204348623105, 528597552113, 1364545143938, 3515960193715
Offset: 20

Views

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Keywords

Crossrefs

Column k=6 of A244523.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
          `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
           b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
        end:
    a:= n-> b(n-1$2, 6$2) -b(n-1$2, 5$2):
    seq(a(n), n=20..60);

A245752 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 7.

Original entry on oeis.org

3, 23, 114, 474, 1780, 6179, 20363, 64441, 197653, 591131, 1732165, 4989933, 14171244, 39760411, 110402589, 303808762, 829504935, 2249326273, 6062516975, 16252409052, 43361162336, 115191492778, 304834916107, 803891596292, 2113302899765, 5539657831304
Offset: 25

Views

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Keywords

Crossrefs

Column k=7 of A244523.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
          `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
           b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
        end:
    a:= n-> b(n-1$2, 7$2) -b(n-1$2, 6$2):
    seq(a(n), n=25..60);

A245753 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 8.

Original entry on oeis.org

1, 19, 113, 564, 2362, 9062, 32336, 109826, 358021, 1131089, 3480858, 10484995, 31012892, 90329292, 259621691, 737665484, 2074944123, 5785110380, 16003477783, 43963346701, 120021805899, 325835717520, 880125679307, 2366498068034, 6336725620724, 16903670460151
Offset: 30

Views

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Keywords

Crossrefs

Column k=8 of A244523.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
          `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
           b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
        end:
    a:= n-> b(n-1$2, 8$2) -b(n-1$2, 7$2):
    seq(a(n), n=30..60);

A245754 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 9.

Original entry on oeis.org

6, 63, 400, 2003, 8749, 34754, 128907, 453653, 1531833, 5001990, 15888511, 49313315, 150075356, 449080945, 1324309374, 3855721297, 11100436053, 31641094693, 89395066791, 250570651706, 697347017396, 1928281739720, 5300986280922, 14495618055341, 39446850848309
Offset: 36

Views

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Keywords

Crossrefs

Column k=9 of A244523.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
          `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
           b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
        end:
    a:= n-> b(n-1$2, 9$2) -b(n-1$2, 8$2):
    seq(a(n), n=36..70);

A245755 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 10.

Original entry on oeis.org

15, 147, 1003, 5286, 24396, 101768, 395410, 1452251, 5104104, 17300428, 56912396, 182543809, 573014123, 1765525901, 5352351017, 15996845972, 47213204699, 137795770991, 398168121417, 1140238386377, 3238947787201, 9133172049405, 25582174762816, 71220487524663
Offset: 42

Views

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Keywords

Crossrefs

Column k=10 of A244523.

Programs

  • Maple
    b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
          `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
           b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
        end:
    a:= n-> b(n-1$2, 10$2) -b(n-1$2, 9$2):
    seq(a(n), n=42..70);
Showing 1-9 of 9 results.