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A170744
Expansion of g.f.: (1+x)/(1-24*x).
50
1, 25, 600, 14400, 345600, 8294400, 199065600, 4777574400, 114661785600, 2751882854400, 66045188505600, 1585084524134400, 38042028579225600, 913008685901414400, 21912208461633945600, 525893003079214694400, 12621432073901152665600, 302914369773627663974400
OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n} A097805(n,k)*(-1)^(n-k)*25^k. - Philippe Deléham, Dec 04 2009
a(0) = 1; for n>0, a(n) = 25*24^(n-1). - Vincenzo Librandi, Dec 05 2009
E.g.f.: (25*exp(24*x) - 1)/24. - G. C. Greubel, Sep 25 2019
MAPLE
k:=25; seq(`if`(n=0, 1, k*(k-1)^(n-1)), n = 0..25); # G. C. Greubel, Sep 25 2019
MATHEMATICA
Join[{1}, NestList[24#&, 25, 30]] (* Harvey P. Dale, Jan 19 2019 *)
PROG
(Python) for i in range(31):print(i, 25*24**(i-1) if i>0 else 1) # Kenny Lau, Aug 03 2017
(PARI) vector(26, n, k=25; if(n==1, 1, k*(k-1)^(n-2))) \\ G. C. Greubel, Sep 25 2019
(Magma) k:=25; [1] cat [k*(k-1)^(n-1): n in [1..25]]; // G. C. Greubel, Sep 25 2019
(Sage) k=25; [1]+[k*(k-1)^(n-1) for n in (1..25)] # G. C. Greubel, Sep 25 2019
(GAP) k:=25;; Concatenation([1], List([1..25], n-> k*(k-1)^(n-1) )); # G. C. Greubel, Sep 25 2019
CROSSREFS
Sequence in context: A170610 A170658 A170706 * A362473 A218727 A264209
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Dec 04 2009
STATUS
approved