OFFSET
1,1
COMMENTS
Multiples of 9 with final digit 9.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..2000
Index entries for linear recurrences with constant coefficients, signature (2,-1).
FORMULA
a(n) = a(n-1) + 90.
From G. C. Greubel, Jul 18 2017: (Start)
G.f.: 9*(19*x-9)/(x-1)^2.
E.g.f.: 9*(10*x - 9)*exp(x). (End) [G.f. corrected by Georg Fischer, May 12 2019]
MATHEMATICA
Table[90*n-81, {n, 0, 50}] (* G. C. Greubel, Jul 18 2017 *)
PROG
(Magma) [90*n-81: n in [1..50]]; // Vincenzo Librandi, Jun 19 2011
(PARI) for(n=1, 1e2, a=90*n-81; print1(a, ", ")) \\ Felix Fröhlich, Jul 07 2014
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Odimar Fabeny, Jun 06 2008
EXTENSIONS
More terms from Reinhard Zumkeller, Jun 22 2008
STATUS
approved