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A155662
a(n) = 11^n - 7^n + 1.
12
1, 5, 73, 989, 12241, 144245, 1653913, 18663629, 208594081, 2317594085, 25654949353, 283334343869, 3124587089521, 34425823133525, 379071610510393, 4172500607905709, 45916496933002561, 505214397985306565, 5558288899894321033, 61147691553229173149
OFFSET
0,2
FORMULA
G.f.: 1/(1-11*x) - 1/(1-7*x) + 1/(1-x).
E.g.f.: e^(11*x) - e^(7*x) + e^x.
a(n) = 18*a(n-1) - 77*a(n-2) + 60; a(0)=1, a(1)=5. - Vincenzo Librandi, Jul 21 2010
MATHEMATICA
Table[11^n-7^n+1, {n, 0, 30}] (* Harvey P. Dale, Jan 16 2023 *)
PROG
(PARI) a(n)=11^n-7^n+1 \\ Charles R Greathouse IV, Jun 11 2015
KEYWORD
nonn,easy
AUTHOR
Mohammad K. Azarian, Jan 31 2009
STATUS
approved