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.

Previous Showing 11-15 of 15 results.

A038092 Number of n-node rooted identity trees of height 8.

Original entry on oeis.org

1, 7, 27, 82, 221, 553, 1323, 3078, 7019, 15765, 34992, 76922, 167697, 363020, 780937, 1670786, 3557060, 7539856, 15918972, 33490067, 70226358, 146822144, 306121101, 636648253, 1320964417, 2734901341, 5650875038, 11653922283, 23991828701, 49310264440
Offset: 9

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Author

Christian G. Bower, Jan 04 1999

Keywords

Comments

The number of terms with a(n)>0 is A038093(8) - 8. - Alois P. Heinz, Sep 22 2013

Crossrefs

Column k=8 of A227819.

Programs

  • Mathematica
    f[n_]:=Nest[CoefficientList[Series[Product[(1+x^i)^#[[i]],{i,1,Length[#]}],{x,0,50}],x]&,{1},n];Drop[f[8]-PadRight[f[7],Length[f[8]]],8] (* Geoffrey Critzer, Aug 01 2013 *)

Formula

A229403 Number of n-node rooted identity trees of height 9.

Original entry on oeis.org

1, 8, 35, 118, 347, 937, 2396, 5913, 14232, 33628, 78354, 180562, 412369, 934692, 2105002, 4714008, 10504530, 23304653, 51497811, 113391278, 248863010, 544569597, 1188413271, 2587000060, 5618544541, 12176514816, 26336600045, 56858108011, 122538855414
Offset: 10

Views

Author

Alois P. Heinz, Sep 22 2013

Keywords

Comments

The number of terms with a(n)>0 is A038093(9)-9.

Crossrefs

Column k=9 of A227819.

A229404 Number of n-node rooted identity trees of height 10.

Original entry on oeis.org

1, 9, 44, 163, 519, 1502, 4081, 10625, 26836, 66278, 160934, 385647, 914426, 2149634, 5017105, 11638062, 26853653, 61674487, 141063327, 321453345, 730085764, 1653165271, 3733016952, 8408241791, 18894670248, 42368155842, 94814369316, 211789296206, 472262524451
Offset: 11

Views

Author

Alois P. Heinz, Sep 22 2013

Keywords

Comments

The number of terms with a(n)>0 is A038093(10)-10.

Crossrefs

Column k=10 of A227819.

A245090 Number of 2n-node rooted identity trees of height n.

Original entry on oeis.org

0, 1, 1, 2, 8, 34, 149, 672, 3078, 14232, 66278, 310408, 1460390, 6896417, 32668860, 155166468, 738679240, 3523549192, 16837094932, 80580576022, 386187326865, 1853144445292, 8902504243912, 42811658101548, 206072505914938, 992778384676916, 4786621055083592
Offset: 0

Views

Author

Alois P. Heinz, Jul 11 2014

Keywords

Crossrefs

Cf. A227819.

Formula

a(n) = A227819(2n,n).
a(n) ~ c * d^n / sqrt(n), where d = 4.9159375028212..., c = 0.025641919495... . - Vaclav Kotesovec, Jul 12 2014

A245091 Number of (2n+1)-node rooted identity trees of height n.

Original entry on oeis.org

1, 0, 0, 2, 12, 61, 301, 1460, 7019, 33628, 160934, 770109, 3686706, 17661288, 84675601, 406319271, 1951428049, 9380072046, 45124798445, 217252113080, 1046731684143, 5046754081095, 24348794377704, 117547968556766, 567818803946292, 2744396907325759
Offset: 0

Views

Author

Alois P. Heinz, Jul 11 2014

Keywords

Crossrefs

Cf. A227819.

Formula

a(n) = A227819(2n+1,n).
a(n) ~ c * d^n / sqrt(n), where d = 4.9159375028212... (same as for A245090), c = 0.076188269997... . - Vaclav Kotesovec, Jul 12 2014
Previous Showing 11-15 of 15 results.