|
|
A014914
|
|
a(1)=1, a(n) = 25*a(n-1) + n.
|
|
2
|
|
|
1, 27, 678, 16954, 423855, 10596381, 264909532, 6622738308, 165568457709, 4139211442735, 103480286068386, 2587007151709662, 64675178792741563, 1616879469818539089, 40421986745463477240, 1010549668636586931016
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
FORMULA
|
a(1)=1, a(2)=27, a(3)=678, a(n) = 27*a(n-1) - 51*a(n-2) + 25*a(n-3). - Vincenzo Librandi, Oct 19 2012
|
|
MATHEMATICA
|
LinearRecurrence[{27, -51, 25}, {1, 27, 678}, 20] (* Vincenzo Librandi, Oct 19 2012 *)
nxt[{n_, a_}]:={n+1, 25a+n+1}; NestList[nxt, {1, 1}, 20][[All, 2]] (* Harvey P. Dale, Nov 16 2021 *)
|
|
PROG
|
(Magma) I:=[1, 27, 678]; [n le 3 select I[n] else 27*Self(n-1) - 51*Self(n-2)+ 25*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Oct 19 2012
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|