A160156 Partial sums of A007583.
1, 4, 15, 58, 229, 912, 3643, 14566, 58257, 233020, 932071, 3728274, 14913085, 59652328, 238609299, 954437182, 3817748713, 15270994836, 61083979327, 244335917290, 977343669141, 3909374676544, 15637498706155, 62549994824598
Offset: 0
Examples
G.f. = 1 + 4*x + 15*x^2 + 58*x^3 + 229*x^4 + 912*x^5 + 3643*x^6 + ... - _Michael Somos_, Oct 16 2020
Links
- Hacène Belbachir and El-Mehdi Mehiri, Enumerating moves in the optimal solution of the Tower of Hanoi, arXiv:2210.08657 [math.CO], 2022.
- Wolfdieter Lang, Notes on certain inhomogeneous three term recurrences.
- N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS
- Index entries for sequences related to toothpick sequences
- Index entries for linear recurrences with constant coefficients, signature (6,-9,4).
Programs
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Maple
a := proc (n) options operator, arrow: (1/3)*n+1/9+(1/9)*2^(2*n+3) end proc: seq(a(n), n = 0 .. 25); # Emeric Deutsch, Jun 20 2009
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Mathematica
LinearRecurrence[{6,-9,4},{1,4,15},30] (* Harvey P. Dale, Oct 04 2018 *)
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PARI
{a(n) = (2^(2*n + 3) + 3*n + 1)/9}; /* Michael Somos, Oct 16 2020 */
Formula
a(n) = (3n + 1 + 2^(2n+3))/9. - Emeric Deutsch, Jun 20 2009
G.f.: ( -1+2*x ) / ( (-1+4*x)*(x-1)^2 ). - R. J. Mathar, Jun 28 2012
From Wolfdieter Lang, Nov 16 2013: (Start)
a(n) = 6*a(n-1) - 9*a(n-2) + 4*a(n-3), n >= 2, a(-1)=0, a(0)=1, a(1)=4.
a(n) = 5*a(n-1) - 4*a(n-2) -1, n >= 2, a(0)=1, a(1)=4. (End)
a(n) = A034299(2*n). - Michael Somos, Oct 16 2020
Extensions
More terms from Emeric Deutsch, Jun 20 2009
Comments