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.

A215707 n-th derivative of ((x^x)^x)^(x^x) at x=1.

Original entry on oeis.org

1, 1, 6, 33, 228, 1880, 17742, 187124, 2176360, 27617616, 378764280, 5574170712, 87491513304, 1457433784560, 25654258467432, 475431102931080, 9246150139382400, 188172595998890688, 3997389233216787264, 88440294467474068608, 2033755519425292281600
Offset: 0

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Author

Alois P. Heinz, Aug 21 2012

Keywords

Comments

Also n-th derivative of ((x^(x^x))^x)^x, ((x^x)^(x^x))^x, x^(x^x*x^2) at x=1.
First term < 0: a(152).

Crossrefs

Column k=10 of A215703.

Programs

  • Maple
    a:= n-> n!*coeff(series(subs(x=x+1, x^(x^x*x^2) ), x, n+1), x, n):
    seq(a(n), n=0..25);

Formula

E.g.f.: (x+1)^((x+1)^(x+3)).

A215708 n-th derivative of (x^(x^x))^(x^x) at x=1.

Original entry on oeis.org

1, 1, 4, 24, 148, 1180, 10428, 106876, 1198160, 14843808, 198832320, 2877693984, 44545268832, 734929736736, 12852051257472, 237372559264320, 4614124211454720, 94103610003019008, 2008507968212696064, 44748953208031094784, 1038646472528272158720
Offset: 0

Views

Author

Alois P. Heinz, Aug 21 2012

Keywords

Comments

Also n-th derivative of x^((x^x)^2) at x=1.
First term < 0: a(175).

Crossrefs

Column k=11 of A215703.

Programs

  • Maple
    a:= n-> n!*coeff(series(subs(x=x+1, x^((x^x)^2) ), x, n+1), x, n):
    seq(a(n), n=0..25);

Formula

E.g.f.: (x+1)^((x+1)^(2*x+2)).

A215709 n-th derivative of (x^x)^((x^x)^x) at x=1.

Original entry on oeis.org

1, 1, 4, 24, 172, 1420, 13968, 154336, 1914288, 26108208, 388596960, 6251899104, 108088087776, 1995840455232, 39183950494752, 814399382073120, 17856182764554240, 411671923447488768, 9952212794293198080, 251646630845685827328, 6640389412581544588800
Offset: 0

Views

Author

Alois P. Heinz, Aug 21 2012

Keywords

Comments

Also n-th derivative of (x^((x^x)^x))^x = x^(x^(x^2)*x) at x=1.

Crossrefs

Column k=12 of A215703.

Programs

  • Maple
    a:= n-> n!*coeff(series(subs(x=x+1, x^(x^(x^2)*x) ), x, n+1), x, n):
    seq(a(n), n=0..25);

Formula

E.g.f.: (x+1)^((x+1)^(x^2+2*x+2)).

A215710 n-th derivative of x^(((x^x)^x)^x) at x=1.

Original entry on oeis.org

1, 1, 2, 21, 152, 1360, 15174, 184296, 2538584, 39097296, 656793720, 12021152616, 237610299288, 5033625978576, 113810068532328, 2733480292962600, 69463846973884800, 1861656629684769600, 52458209090931835584, 1549997983761108724224, 47908467697220966937600
Offset: 0

Views

Author

Alois P. Heinz, Aug 21 2012

Keywords

Comments

Also n-th derivative of x^(x^(x^3)) at x=1.

Crossrefs

Column k=14 of A215703.

Programs

  • Maple
    a:= n-> n!*coeff(series(subs(x=x+1, x^(x^(x^3)) ), x, n+1), x, n):
    seq(a(n), n=0..25);

Formula

E.g.f.: (x+1)^((x+1)^((x+1)^3)).

A293473 Triangle read by rows, coefficients of polynomials in t = log(x) of the n-th derivative of x^(x^2), evaluated at x = 1. T(n, k) with n >= 0 and 0 <= k <= n.

Original entry on oeis.org

1, 1, 2, 4, 6, 4, 12, 30, 24, 8, 52, 144, 156, 80, 16, 240, 760, 1020, 680, 240, 32, 1188, 4440, 6720, 5640, 2640, 672, 64, 6804, 26712, 47040, 45640, 26880, 9408, 1792, 128, 38960, 175392, 338016, 376320, 261520, 115584, 31360, 4608, 256
Offset: 0

Views

Author

Peter Luschny, Oct 10 2017

Keywords

Examples

			Triangle starts:
0: [   1]
1: [   1,     2]
2: [   4,     6,     4]
3: [  12,    30,    24,     8]
4: [  52,   144,   156,    80,    16]
5: [ 240,   760,  1020,   680,   240,   32]
6: [1188,  4440,  6720,  5640,  2640,  672,   64]
7: [6804, 26712, 47040, 45640, 26880, 9408, 1792, 128]
...
For n = 3, the 3rd derivative of x^(x^2) is p(3,x,t) = 8*t^3*x^3*x^(x^2) + 12*t^2*x^3*x^(x^2) + 6*t*x^3*x^(x^2) + 12*t^2*x*x^(x^2) + x^3*x^(x^2) + 24*t*x*x^(x^2) + 9*x*x^(x^2) + 2*x^(x^2)/x where log(x) is substituted by t. Evaluated at x = 1: p(3,1,t) = 12 + 30*t + 24*t^2 + 8*t^3 with coefficients [12, 30, 24, 8].
		

Crossrefs

T(n, 0) = A215524, T(n, n) = A000079.
More generally, consider the n-th derivative of x^(x^m).
A293472 (m=1), this seq. (m=2), A293474 (m=3).
Cf. A290268.

Programs

  • Maple
    # Function dx in A293472.
    ListTools:-Flatten([seq(dx(2, n), n=0..8)]);
  • Mathematica
    (* Function dx in A293472. *)
    Table[dx[2, n], {n, 0, 7}] // Flatten
Previous Showing 11-15 of 15 results.