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 1-3 of 3 results.

A020060 a(n) = floor( Gamma(n+9/10)/Gamma(9/10) ).

Original entry on oeis.org

1, 0, 1, 4, 19, 94, 559, 3857, 30477, 271252, 2685395, 29270806, 348322596, 4493361500, 62457724853, 930620100318, 14796859595058, 250066927156481, 4476197996101023, 84600142126309335, 1683542828313555774
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Magma
    [Floor(Gamma(n+9/10)/Gamma(9/10)): n in [0..20]]; // G. C. Greubel, Nov 13 2019
    
  • Maple
    Digits := 64:f := proc(n,x) trunc(GAMMA(n+x)/GAMMA(x)); end;
    seq(floor(pochhammer(9/10,n)), n = 0..20); # G. C. Greubel, Nov 13 2019
  • Mathematica
    Floor[Pochhammer[9/10, Range[0, 20]]] (* G. C. Greubel, Nov 13 2019 *)
  • PARI
    vector(21, n, my(x=9/10); gamma(n-1+x)\gamma(x) ) \\ G. C. Greubel, Nov 13 2019
    
  • Sage
    [floor(rising_factorial(9/10, n)) for n in (0..20)] # G. C. Greubel, Nov 13 2019

A020017 Nearest integer to Gamma(n + 3/10)/Gamma(3/10).

Original entry on oeis.org

1, 0, 0, 1, 3, 13, 67, 425, 3103, 25751, 239483, 2466678, 27873456, 342843514, 4559818741, 65205407995, 997642742322, 16261576699844, 281325276907304, 5148252567403659, 99361274550890613, 2017033873383079454
Offset: 0

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Author

Keywords

Comments

Gamma(n + 3/10)/Gamma(3/10) = 1, 3/10, 39/100, 897/1000, 29601/10000, 1272843/100000, 67460679/1000000, ... - R. J. Mathar, Sep 04 2016

Crossrefs

Programs

  • Magma
    [Round(Gamma(n+3/10)/Gamma(3/10)): n in [0..30]]; // G. C. Greubel, Jan 20 2018
  • Maple
    Digits := 64:f := proc(n,x) round(GAMMA(n+x)/GAMMA(x)); end;
  • Mathematica
    Table[Round[Gamma[n + 3/10]/Gamma[3/10]], {n, 0, 50}] (* G. C. Greubel, Jan 20 2018 *)
  • PARI
    for(n=0,30, print1(round(gamma(n+3/10)/gamma(3/10)), ", ")) \\ G. C. Greubel, Jan 20 2018
    

A182831 Joint-rank array of numbers j*r^(i-1), where r=1+sqrt(2), read by antidiagonals.

Original entry on oeis.org

1, 2, 3, 4, 6, 8, 5, 11, 17, 22, 7, 14, 28, 45, 55, 9, 19, 37, 70, 112, 137, 10, 23, 48, 93, 171, 276, 334, 12, 26, 57, 118, 228, 417, 671, 812, 13, 31, 66, 141, 287, 556, 1010, 1627, 1965, 15, 34, 77, 164, 344, 697, 1347, 2444, 3934, 4751, 16, 39
Offset: 1

Views

Author

Clark Kimberling, Dec 07 2010

Keywords

Comments

Joint-rank arrays are defined in the first comment at A182801. (row 1)=A087063. First 3 columns are A020062, A020063, A020064.
Every positive integer occurs exactly once, so that as a sequence, this is a permutation of the positive integers.

Examples

			Northwest corner:
   1  2  4  5 ...
   3  6 11 14 ...
   8 17 28 37 ...
  22 45 70 93 ...
  ...
		

Crossrefs

Cf. A182801.

Programs

  • Mathematica
    T[n_, k_] := Sum[Floor[k*(1 + Sqrt[2])^(n - j)], {j, 1, 100}]; Table[T[k + 1, n - k], {n,1,10}, {k, 0, n-1}]//Flatten (* G. C. Greubel, Aug 18 2018 *)

Formula

T(i,j) = Sum_{n>=1} floor(j*(1+sqrt(2))^(i-n)).
Showing 1-3 of 3 results.