login
A360416
a(n) = 8*n^2 - 9*n + 3.
3
3, 2, 17, 48, 95, 158, 237, 332, 443, 570, 713, 872, 1047, 1238, 1445, 1668, 1907, 2162, 2433, 2720, 3023, 3342, 3677, 4028, 4395, 4778, 5177, 5592, 6023, 6470, 6933, 7412, 7907, 8418, 8945, 9488, 10047, 10622, 11213, 11820, 12443, 13082, 13737, 14408, 15095
OFFSET
0,1
COMMENTS
This is one of the four quadratic sequences that, interleaved, yield A360418.
FORMULA
From Elmo R. Oliveira, Jan 28 2025: (Start)
G.f.: (3 - 7*x + 20*x^2)/(1 - x)^3.
E.g.f.: (3 - x + 8*x^2)*exp(x).
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n >= 3.
a(n) = A360418(4*n-2) for n >= 1. (End)
MATHEMATICA
Table[8*n^2 - 9*n + 3, {n, 0, 100}]
CROSSREFS
Sequence in context: A342140 A126354 A361084 * A158939 A173795 A249769
KEYWORD
nonn,easy
AUTHOR
James Propp, Feb 06 2023
EXTENSIONS
a(0)=3 prepended and more terms from Elmo R. Oliveira, Jan 28 2025
STATUS
approved