OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
FORMULA
G.f.: -2*x^2/(1-x)^3 + (9/(1-x)^2)*Sum_{k=0..infinity} (10^(2*d)*x^(10^d)-(10^(2*d)-10^d)*x^(1+10^d)). - Robert Israel, Aug 18 2019
EXAMPLE
a(45) = 2475 as 10's complement of 45 is 100-45 = 55 and 45*55 = 2475.
MAPLE
seq((10^(1+ilog10(n))-n)*n, n=1..100); # Robert Israel, Aug 18 2019
MATHEMATICA
#*(10^(IntegerLength[#]) - #) & /@ Range[39] (* Jayanta Basu, Aug 07 2013 *)
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Amarnath Murthy, Mar 08 2002
STATUS
approved