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A278927
a(n) = permanent M_n where M_n is the n X n matrix m(i,j) = 2*i + j.
1
1, 3, 38, 1116, 59392, 5004720, 613252320, 103050420480, 22752244279296, 6388491978086400, 2223423557203968000, 939489529945565491200, 473789563269835667374080, 281112352557447776249364480, 193857685859605294233907200000, 153758529080702011472247521280000
OFFSET
0,2
LINKS
FORMULA
a(n) ~ c * d^n * n!^2 / sqrt(n), where d = 3.63208011334048289... and c = 1.47836065972078...
MAPLE
with(LinearAlgebra):
a:= n-> `if`(n=0, 1, Permanent(Matrix(n, (i, j)-> 2*i+j))):
seq(a(n), n=0..16);
MATHEMATICA
Flatten[{1, Table[Permanent[Table[2*i+j, {i, 1, n}, {j, 1, n}]], {n, 1, 15}]}]
PROG
(PARI) {a(n) = matpermanent(matrix(n, n, i, j, 2*i+j))}
for(n=0, 20, print1(a(n), ", ")) \\ Vaclav Kotesovec, Dec 21 2018
CROSSREFS
Cf. A204249.
Sequence in context: A263332 A335529 A062155 * A099022 A229365 A136638
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Dec 01 2016
STATUS
approved