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A081590
Fourth row of Pascal-(1,5,1) array A081580.
4
1, 19, 145, 595, 1585, 3331, 6049, 9955, 15265, 22195, 30961, 41779, 54865, 70435, 88705, 109891, 134209, 161875, 193105, 228115, 267121, 310339, 357985, 410275, 467425, 529651, 597169, 670195, 748945, 833635, 924481, 1021699, 1125505
OFFSET
0,2
FORMULA
a(n) = 1 + 36*n - 54*n^2 + 36*n^3.
G.f.: (1+5x)^3/(1-x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4); a(0)=1, a(1)=19, a(2)=145, a(3)=595. - Harvey P. Dale, Sep 07 2011
MATHEMATICA
Table[36n^3-54n^2+36n+1, {n, 0, 50}] (* or *) LinearRecurrence[{4, -6, 4, -1}, {1, 19, 145, 595}, 50] (* Harvey P. Dale, Sep 07 2011 *)
PROG
(Magma) [1+36*n-54*n^2+36*n^3: n in [0..40]]; // Vincenzo Librandi, Sep 07 2011
CROSSREFS
Cf. A081589.
Sequence in context: A110694 A107962 A002615 * A093646 A264679 A200530
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Mar 23 2003
STATUS
approved