OFFSET
0,2
COMMENTS
a(n) is also the number of acyclic orientations of the complete bipartite graph K_{9,n}. - Vincent Pilaud, Sep 16 2020
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..994
Index entries for linear recurrences with constant coefficients, signature (54,-1266,16884,-140889,761166,-2655764,5753736,-6999840,3628800).
FORMULA
a(n) = 362880*10^n - 1451520*9^n + 2328480*8^n - 1905120*7^n + 834120*6^n - 186480*5^n + 18150*4^n - 510*3^n + 2^n.
MATHEMATICA
Table[362880*10^n - 1451520*9^n + 2328480*8^n - 1905120*7^n + 834120*6^n - 186480*5^n + 18150*4^n - 510*3^n + 2^n, {n, 0, 20}] (* Indranil Ghosh, Mar 19 2017 *)
LinearRecurrence[{54, -1266, 16884, -140889, 761166, -2655764, 5753736, -6999840, 3628800}, {1, 512, 38854, 1455278, 37712866, 779305142, 13821281314, 219680806598, 3216941445106}, 20] (* Harvey P. Dale, Dec 18 2022 *)
PROG
(PARI) a(n) = 362880*10^n - 1451520*9^n + 2328480*8^n - 1905120*7^n + 834120*6^n - 186480*5^n + 18150*4^n - 510*3^n + 2^n; \\ Indranil Ghosh, Mar 19 2017
(Python) def a(n): return 362880*10**n - 1451520*9**n + 2328480*8**n - 1905120*7**n + 834120*6**n - 186480*5**n + 18150*4**n - 510*3**n + 2**n # Indranil Ghosh, Mar 19 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Mar 18 2017
STATUS
approved