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 1-2 of 2 results.

A187361 Pell trisection: Pell(3*n+1), n >= 0.

Original entry on oeis.org

1, 12, 169, 2378, 33461, 470832, 6625109, 93222358, 1311738121, 18457556052, 259717522849, 3654502875938, 51422757785981, 723573111879672, 10181446324101389, 143263821649299118, 2015874949414289041, 28365513113449345692, 399133058537705128729, 5616228332641321147898
Offset: 0

Views

Author

Wolfdieter Lang, Mar 09 2011

Keywords

Comments

For the general computation of the o.g.f.s for the trisection of a sequence, given by its real o.g.f., see a Wolfdieter Lang comment under A187357.

Crossrefs

Cf. A142588 (Pell(3*n)), A187362 (Pell(3*n+2)).

Programs

  • Mathematica
    Table[Fibonacci[3n + 1, 2], {n, 0, 20}] (* Vladimir Reshetnikov, Sep 16 2016 *)
    LinearRecurrence[{14,1},{1,12},20] (* Harvey P. Dale, Jul 06 2023 *)
  • PARI
    Vec((1-2*x)/(1-14*x-x^2) + O(x^20)) \\ Colin Barker, Jan 25 2016

Formula

a(n) = Pell(3*n+1), n >= 0, with Pell(n):=A000129(n).
O.g.f.: (1-2*x)/(1-14*x-x^2).
a(n) = 14*a(n-1) + a(n-2), a(0)= 1, a(1)=12.
a(n) = (((7-5*sqrt(2))^n*(-1+sqrt(2))+(1+sqrt(2))*(7+5*sqrt(2))^n))/(2*sqrt(2)). - Colin Barker, Jan 25 2016

A187362 Pell trisection: Pell(3*n+2), n >= 0.

Original entry on oeis.org

2, 29, 408, 5741, 80782, 1136689, 15994428, 225058681, 3166815962, 44560482149, 627013566048, 8822750406821, 124145519261542, 1746860020068409, 24580185800219268, 345869461223138161, 4866752642924153522, 68480406462161287469, 963592443113182178088, 13558774610046711780701
Offset: 0

Views

Author

Wolfdieter Lang, Mar 09 2011

Keywords

Comments

For the general trisection of a sequence see a Wolfdieter Lang comment under A187357.

Crossrefs

Cf. A142588 (Pell(3n)), A187361 (Pell(3n+1)).

Programs

  • Mathematica
    Table[Fibonacci[3n + 2, 2], {n, 0, 20}] (* Vladimir Reshetnikov, Sep 16 2016 *)
  • PARI
    Vec((2+x)/(1-14*x-x^2) + O(x^20)) \\ Colin Barker, Jan 25 2016

Formula

a(n) = Pell(3*n+2), n >= 0, with Pell(n):=A000129(n).
O.g.f.: (2+x)/(1-14*x-x^2).
a(n) = 14*a(n-1) + a(n-2), a(-1)=1, a(0)=2.
a(n) = (((7-5*sqrt(2))^n*(-3+2*sqrt(2)) + (3+2*sqrt(2))*(7+5*sqrt(2))^n)) / (2*sqrt(2)). - Colin Barker, Jan 25 2016
Showing 1-2 of 2 results.