login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A348621
The number of additions required to compute the permanent of general n X n matrices using Ryser's formula without Gray code ordering.
0
0, 4, 21, 82, 275, 836, 2373, 6406, 16647, 41992, 103433, 249866, 593931, 1392652, 3227661, 7405582, 16842767, 38010896, 85196817, 189792274, 420478995, 926941204, 2034237461, 4445962262, 9680453655, 21005074456, 45432700953, 97978941466, 210721832987, 452045307932
OFFSET
1,2
REFERENCES
Herbert John Ryser, Combinatorial Mathematics, volume 14 of Carus Mathematical Monographs. American Mathematical Soc., (1963), pp. 24-28.
LINKS
Han Mao Kiah, Alexander Vardy and Hanwen Yao, Computing Permanents on a Trellis, arXiv:2107.07377 [cs.IT], 2021. See Table 1 p. 3.
FORMULA
a(n) = (n^2 - 2*n + 2)*2^(n-1) + n - 2.
a(n) = n*A000337(n-1) + A000079(n) - 2.
a(n) = 8*a(n-1) - 25*a(n-2) + 38*a(n-3) - 28*a(n-4) + 8*a(n-5) for n > 5.
O.g.f.: x^2*(4 - 11*x + 14*x^2 - 8*x^3)/((1 - x)^2*(1 - 2*x)^3).
E.g.f.: 1 + exp(x)*(x - 2) + exp(2*x)*(2*x^2 - x + 1).
MATHEMATICA
LinearRecurrence[{8, -25, 38, -28, 8}, {0, 4, 21, 82, 275}, 30]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Stefano Spezia, Oct 25 2021
STATUS
approved