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A345701
a(n) = 3*n^3 - 1.
1
-1, 2, 23, 80, 191, 374, 647, 1028, 1535, 2186, 2999, 3992, 5183, 6590, 8231, 10124, 12287, 14738, 17495, 20576, 23999, 27782, 31943, 36500, 41471, 46874, 52727, 59048, 65855, 73166, 80999, 89372, 98303, 107810, 117911, 128624, 139967, 151958, 164615, 177956, 191999
OFFSET
0,2
COMMENTS
Compare to A056220(n) = 2*n^2 - 1.
FORMULA
a(n) = A117642(n) - 1.
G.f.: (4*x^3+9*x^2+6*x-1)/(x-1)^4. - Alois P. Heinz, Jun 24 2021
E.g.f.: exp(x)*(-1 + 3*x + 9*x^2 + 3*x^3). - Stefano Spezia, Jun 24 2021
MATHEMATICA
Table[3 n^3 - 1, {n, 100}]
CROSSREFS
Sequence in context: A217113 A042679 A354691 * A209194 A097232 A339474
KEYWORD
sign,easy
AUTHOR
Tanya Khovanova, Jun 24 2021
STATUS
approved