OFFSET
1,1
LINKS
FORMULA
a(n) = 10*a(n-1) - 23 with n > 1, a(1) = 7.
a(n) = 11*a(n-1) - 10*a(n-2). G.f.: -x*(30*x-7)/((x-1)*(10*x-1)). [Colin Barker, Jan 24 2013]
E.g.f.: exp(x)*(4*exp(9*x) + 23)/9. - Elmo R. Oliveira, Sep 09 2024
MATHEMATICA
LinearRecurrence[{11, -10}, {7, 47}, 30] (* or *) Table[FromDigits[ PadLeft[ {7}, n, 4]], {n, 30}] (* Harvey P. Dale, Dec 27 2014 *)
PROG
(PARI) a(n)=4*10^n\9+3 \\ Charles R Greathouse IV, Jan 11 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Feb 24 2010
EXTENSIONS
a(19)-a(21) from Elmo R. Oliveira, Sep 09 2024
STATUS
approved