OFFSET
1,3
COMMENTS
Row 9 of A187162.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..50
FORMULA
Empirical: a(n) = 387966*n^3 - 2452704*n^2 + 4766544*n - 2833872 for n>7.
Conjectures from Colin Barker, Apr 21 2018: (Start)
G.f.: 6*x^3*(27836 + 224216*x + 196068*x^2 - 37336*x^3 - 32904*x^4 + 4576*x^5 + 4625*x^6 + 836*x^7 + 49*x^8) / (1 - x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>11.
(End)
CROSSREFS
KEYWORD
nonn,walk
AUTHOR
R. H. Hardin, Mar 06 2011
STATUS
approved