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A056578
a(n) = 1 + 2n + 3n^2 + 4n^3.
15
1, 10, 49, 142, 313, 586, 985, 1534, 2257, 3178, 4321, 5710, 7369, 9322, 11593, 14206, 17185, 20554, 24337, 28558, 33241, 38410, 44089, 50302, 57073, 64426, 72385, 80974, 90217, 100138, 110761, 122110, 134209, 147082, 160753, 175246
OFFSET
0,2
FORMULA
a(n) = (A053699(n+1) - A053699(n-1))/2 - 4n - 1.
G.f.: (1 + 6*x + 15*x^2 + 2*x^3)/(1-x)^4. - Colin Barker, Jan 10 2012
EXAMPLE
For n>4 this is 4321 translated from base n to base 10.
MATHEMATICA
f[n_]:=1+2*n+3*n^2+4*n^3; lst={}; Do[AppendTo[lst, f[n]], {n, 0, 5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Feb 12 2010 *)
CROSSREFS
Note: 1 + 2x + 3x^2 + 4x^3 is the first derivative of 1 + x + x^2 + x^3 + x^4, i.e., A053699. Cf. A000012, A005408, A056109, A056579.
Sequence in context: A045770 A217165 A154066 * A370216 A307904 A226797
KEYWORD
easy,nonn
AUTHOR
Henry Bottomley, Jun 29 2000
STATUS
approved