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A030441
Values of Newton-Gregory forward interpolating polynomial (1/3)*(2*n - 3)*(2*n^2 - 3*n + 4).
1
-4, -1, 2, 13, 40, 91, 174, 297, 468, 695, 986, 1349, 1792, 2323, 2950, 3681, 4524, 5487, 6578, 7805, 9176, 10699, 12382, 14233, 16260, 18471, 20874, 23477, 26288, 29315, 32566, 36049, 39772, 43743, 47970, 52461, 57224, 62267, 67598, 73225, 79156, 85399
OFFSET
0,1
FORMULA
a(n) - A177342(n-1) = (n-1)^2, with n>1. For n=6, a(6) - A177342(5) = 174 - 149 = 5^2. - Bruno Berselli, May 23 2010
a(n) = 4*a(n-1)-6*a(n-2)+4*a(n-3)-a(n-4). - Colin Barker, May 18 2014
G.f.: (15*x^3-18*x^2+15*x-4) / (x-1)^4. - Colin Barker, May 18 2014
a(n) = A059259(2*n,3), n>1. - Mathew Englander, May 17 2014
MATHEMATICA
LinearRecurrence[{4, -6, 4, -1}, {-4, -1, 2, 13}, 50] (* Harvey P. Dale, Apr 20 2015 *)
PROG
(PARI) a(n) = (1/3)*(2*n-3)*(2*n^2-3*n+4); \\ Michel Marcus, May 18 2014
CROSSREFS
Equals A030434 shifted left twice.
Sequence in context: A159756 A110559 A365455 * A298570 A284771 A283042
KEYWORD
sign,easy
AUTHOR
Ilias.Kotsireas(AT)lip6.fr (Ilias Kotsireas)
STATUS
approved