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 1-4 of 4 results.

A198478 a(n) = 9^n * n^9.

Original entry on oeis.org

0, 9, 41472, 14348907, 1719926784, 115330078125, 5355700839936, 193010051319183, 5777633090469888, 150094635296999121, 3486784401000000000, 73994897046174912819, 1457274373159131021312, 26955214582765006137717
Offset: 0

Views

Author

Vincenzo Librandi, Oct 27 2011

Keywords

Crossrefs

Programs

  • Magma
    [9^n*n^9: n in [0..20]]
    
  • Mathematica
    Table[9^n*n^9, {n, 0, 20}] (* G. C. Greubel, May 17 2022 *)
  • SageMath
    [9^n*n^9 for n in (0..20)] # G. C. Greubel, May 17 2022

Formula

G.f.: 9*x*(1 + 4518*x + 1183248*x^2 + 64322586*x^3 + 1024762590*x^4 + 5210129466*x^5 + 7763290128*x^6 + 2401050438*x^7 + 43046721*x^8)/(1 - 9*x)^10. - Colin Barker, Apr 30 2013
a(n) = A001019(n)*A001017(n). - Michel Marcus, May 18 2022

A198479 a(n) = 10^n * n^10.

Original entry on oeis.org

0, 10, 102400, 59049000, 10485760000, 976562500000, 60466176000000, 2824752490000000, 107374182400000000, 3486784401000000000, 100000000000000000000, 2593742460100000000000, 61917364224000000000000
Offset: 0

Views

Author

Vincenzo Librandi, Oct 27 2011

Keywords

Crossrefs

Programs

  • Magma
    [10^n*n^10: n in [0..20]]
    
  • Mathematica
    Table[10^n*n^10, {n,0,20}] (* G. C. Greubel, May 17 2022 *)
  • SageMath
    [10^n*n^10 for n in (0..20)] # G. C. Greubel, May 17 2022

Formula

G.f.: 10*x*(1 + 10*x)*(1 + 10120*x + 4682800*x^2 + 408364000*x^3 + 9019900000*x^4 + 40836400000*x^5 + 46828000000*x^6 + 10120000000*x^7 + 100000000*x^8)/ (1-10*x)^11. - Colin Barker, May 01 2013
a(n) = A011557(n)*A008454(n). - Michel Marcus, May 18 2022

A198402 a(n) = 5^n * n^5.

Original entry on oeis.org

0, 5, 800, 30375, 640000, 9765625, 121500000, 1313046875, 12800000000, 115330078125, 976562500000, 7863818359375, 60750000000000, 453238525390625, 3282617187500000, 23174285888671875, 160000000000000000, 1083264923095703125
Offset: 0

Views

Author

Vincenzo Librandi, Oct 27 2011

Keywords

Crossrefs

Sequences of the form n^m*m^n: A001477 (m=1), A007758 (m=2), A062074 (m=3), A062075 (m=4), this sequence (m=5), A198403 (m=6), A098803 (m=7), A198404 (m=8), A198478 (m=9), A198479 (m=10), A098880 (m=11).

Programs

  • Magma
    [5^n*n^5: n in [0..20]]
    
  • Mathematica
    With[{m = 5}, Table[n^m*m^n, {n, 0, 30}]] (* G. C. Greubel, May 18 2022 *)
  • PARI
    a(n)=5^n*n^5 \\ Charles R Greathouse IV, Jul 06 2017
    
  • SageMath
    m=5; [n^m*m^n for n in (0..30)] # G. C. Greubel, May 18 2022

Formula

G.f.: 5*x*(1 + 130*x + 1650*x^2 + 3250*x^3 + 625*x^4)/(1-5*x)^6. - Colin Barker, Apr 30 2013
E.g.f.: 5*x*(1 + 75*x + 625*x^2 + 1250*x^3 + 625*x^4)*exp(5*x). - G. C. Greubel, May 18 2022
a(n) = A000351(n)*A000584(n). - Michel Marcus, May 19 2022

A198403 a(n) = 6^n * n^6.

Original entry on oeis.org

0, 6, 2304, 157464, 5308416, 121500000, 2176782336, 32934190464, 440301256704, 5355700839936, 60466176000000, 642717115324416, 6499837226778624, 63041475422674944, 590045794670739456, 5355700839936000000
Offset: 0

Views

Author

Vincenzo Librandi, Oct 27 2011

Keywords

Crossrefs

Sequences of the form n^m*m^n: A001477 (m=1), A007758 (m=2), A062074 (m=3), A062075 (m=4), A198402 (m=5), this sequence (m=6), A098803 (m=7), A198404 (m=8), A198478 (m=9), A198479 (m=10), A098880 (m=11).

Programs

Formula

G.f.: 6*x*(1 + 336*x + 8856*x^2 + 12096*x^3 + 1296*x^4)/(1-6*x)^7. - Colin Barker, Apr 30 2013
E.g.f.: 6*x*(1 + 186*x + 3240*x^2 + 14040*x^3 + 19440*x^4 + 7776*x^5)*exp(6*x). - G. C. Greubel, May 18 2022
a(n) = A000400(n)*A001014(n). - Michel Marcus, May 19 2022
a(n) = 42*a(n-1) - 756*a(n-2) + 7560*a(n-3) - 45360*a(n-4) + 163296*a(n-5) - 326592*a(n-6) + 279936*a(n-7). - Wesley Ivan Hurt, Sep 04 2022
Showing 1-4 of 4 results.