login
A136306
a(n) = a(n-1)*(10^K) + n*a(n-1); a(0)=1; K=floor(log_10 (n*a(n-1))).
1
1, 2, 6, 78, 8112, 81160560, 8116056486963360, 81160564869633656812395408743520, 8116056486963365681239540874352649284518957069254499163269948160
OFFSET
0,2
COMMENTS
Sequence generalized :
a(n)=[a(n-1)*B^F(a(n-1),n)]+G(a(n-1),n); a(0)=1; F(t),G(t)integer functions.
FORMULA
a(n)=a(n-1)*(10^K) + n + a(n-1); a(0)=1; K=floor(log_10 n + a(n-1)) + 1.
MAPLE
A136306 := proc(n)
option remember;
local k ;
if n = 0 then
1;
else
if n*procname(n-1) < 1 then
k := 0;
else
k := floor(log[10](n*procname(n-1))) ;
end if ;
procname(n-1)*(n+10^k) ;
end if;
end proc:
seq(A136306(n), n=0..10) ; # R. J. Mathar, Jun 19 2021
PROG
(PARI) a(n) = if (n==0, 1, my(x=a(n-1), K=log(n*x)\log(10)); x*(10^K) + n*x); \\ Michel Marcus, Mar 16 2022
CROSSREFS
Sequence in context: A262279 A327052 A231508 * A274825 A376059 A376061
KEYWORD
easy,nonn
AUTHOR
Ctibor O. Zizka, Mar 22 2008
EXTENSIONS
Offset corrected by R. J. Mathar, Jun 19 2021
More terms from Michel Marcus, Mar 16 2022
STATUS
approved