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 1-6 of 6 results.

A012814 Take every 5th term of Padovan sequence A000931, beginning with the third term.

Original entry on oeis.org

0, 1, 5, 21, 86, 351, 1432, 5842, 23833, 97229, 396655, 1618192, 6601569, 26931732, 109870576, 448227521, 1828587033, 7459895657, 30433357674, 124155792775, 506505428836, 2066337330754, 8429820731201, 34390259761825, 140298353215075, 572360547759276, 2334999585697905
Offset: 0

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Author

Keywords

Examples

			G.f. = x + 5*x^2 + 21*x^3 + 86*x^4 + 351*x^5 + 1432*x^6 + 5842*x^7 + ...
		

Crossrefs

Programs

  • Magma
    I:=[0, 1, 5 ]; [n le 3 select I[n] else 5*Self(n-1)-4*Self(n-2)+Self(n-3): n in [1..40]]; // Vincenzo Librandi, Feb 03 2012
  • Mathematica
    LinearRecurrence[{5, -4, 1}, {0, 1, 5}, 25] (* Vincenzo Librandi, Feb 03 2012 *)

Formula

a(n+3) = 5*a(n+2) - 4*a(n+1) + a(n).
a(n) = A000931(5*n+2).
G.f.: x/(1-5*x+4*x^2-x^3). - Colin Barker, Feb 03 2012
a(n) = A012855(n+4) - A012855(n+3).

Extensions

Initial term 0 added by Colin Barker, Feb 03 2012

A012864 Take every 5th term of Padovan sequence A000931, beginning with the first term.

Original entry on oeis.org

1, 1, 3, 12, 49, 200, 816, 3329, 13581, 55405, 226030, 922111, 3761840, 15346786, 62608681, 255418101, 1042002567, 4250949112, 17342153393, 70748973084, 288627200960, 1177482265857, 4803651498529, 19596955630177
Offset: 0

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Author

Keywords

Crossrefs

Cf. A012855.

Programs

  • Magma
    I:=[1, 1, 3]; [n le 3 select I[n] else 5*Self(n-1)-4*Self(n-2)+Self(n-3): n in [1..30]]; // Vincenzo Librandi, Apr 18 2012
  • Mathematica
    LinearRecurrence[{5,-4, 1},{1,1,3},30] (* Vincenzo Librandi, Apr 18 2012 *)

Formula

a(n+3) = 5*a(n+2) - 4*a(n+1) + a(n).
O.g.f.: (1-4x+2x^2)/(1-5x+4x^2-x^3). a(n+1)=A012772(n). - R. J. Mathar, May 28 2008

A176476 Partial sums of A012814.

Original entry on oeis.org

0, 1, 6, 27, 113, 464, 1896, 7738, 31571, 128800, 525455, 2143647, 8745216, 35676948, 145547524, 593775045, 2422362078, 9882257735, 40315615409, 164471408184, 670976837020, 2737314167774, 11167134898975, 45557394660800, 185855747875875, 758216295635151
Offset: 0

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Author

Carmine Suriano, Apr 18 2010

Keywords

Comments

Old name was "a(n) is the minimum integer that can be expressed as the sum of n Padovan numbers (see A000931)".
Lim_{n -> infinity} a(n+1)/a(n) = p^5 = 4.0795956..., where p is the plastic constant (A060006).

Examples

			a(5) = A000931(2) + A000931(7) + A000931(12) + A000931(17) + A000931(22) + A000931(27) = 0 + 1 + 5 + 21 + 86 + 351 = 464.
		

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{6,-9,5,-1},{0,1,6,27},30] (* Harvey P. Dale, Feb 08 2025 *)
  • PARI
    a(n) = my(v=vector(n+1), u=[0,1,6,27]); for(k=1, n+1, v[k]=if(k<=4, u[k], 5*v[k-1] - 4*v[k-2] + v[k-3] + 1)); v[n+1] \\ Jianing Song, Feb 04 2019

Formula

a(n) = A012855(n+3) - 1. a(n) = 6*a(n-1) - 9*a(n-2) + 5*a(n-3) - a(n-4). - R. J. Mathar, Oct 18 2010
G.f.: x/(1 - 6*x + 9*x^2 - 5*x^3 + x^4). - Colin Barker, Feb 03 2012
From Jianing Song, Feb 04 2019: (Start)
a(n+3) = 5*a(n+2) - 4*a(n+1) + a(n) + 1.
a(n) = Sum_{k=0..n} A012814(k) = Sum_{k=0..n} A000931(5*k+2). (End)

Extensions

New name, more terms and a(0) = 0 prepended by Jianing Song, Feb 04 2019

A012866 a(n+3) = 5*a(n+2)-4*a(n+1)+a(n).

Original entry on oeis.org

0, 1, 2, 6, 23, 93, 379, 1546, 6307, 25730, 104968, 428227, 1746993, 7127025, 29075380, 118615793, 483904470, 1974134558, 8053670703, 32855719753, 134038050511, 546821044246, 2230808738939, 9100797568222
Offset: 0

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Author

Keywords

Crossrefs

Cf. A012855.

Formula

G.f. x*(-1+3*x) / ( -1+5*x-4*x^2+x^3 ). - R. J. Mathar, Dec 22 2011
a(n) = A012814(n)-3*A012814(n-1). - R. J. Mathar, Sep 20 2012

A012880 a(n+3) = 5*a(n+2)-4*a(n+1)+a(n).

Original entry on oeis.org

0, 1, 3, 11, 44, 179, 730, 2978, 12149, 49563, 202197, 824882, 3365185, 13728594, 56007112, 228486369, 932131991, 3802721591, 15513566360, 63289077427, 258193843286, 1053326473082, 4297146069693, 17530618299423
Offset: 0

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Author

Keywords

Crossrefs

Cf. A012855.

Formula

G.f. x*(-1+2*x) / ( -1+5*x-4*x^2+x^3 ). a(n) = A012814(n)-2*A012814(n-1). - R. J. Mathar, Sep 20 2012

A012886 a(n+3) = 5*a(n+2)-4*a(n+1)+a(n).

Original entry on oeis.org

1, 2, 3, 8, 30, 121, 493, 2011, 8204, 33469, 136540, 557028, 2272449, 9270673, 37820597, 154292742, 629451995, 2567909604, 10476032782, 42737977489, 174353665921, 711292452431, 2901785575960, 11838111735997
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. A012855.

Programs

  • Mathematica
    LinearRecurrence[{5,-4,1},{1,2,3},30] (* Harvey P. Dale, Sep 16 2023 *)

Formula

G.f. ( -1+3*x+3*x^2 ) / ( -1+5*x-4*x^2+x^3 ). a(n) = -3*A012814(n)+A012814(n+1) -3*A012814(n-1). - R. J. Mathar, Sep 20 2012
Showing 1-6 of 6 results.