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A109910
a(n) = 9's complement of digit reversal of n.
2
9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 8, 88, 78, 68, 58, 48, 38, 28, 18, 8, 7, 87, 77, 67, 57, 47, 37, 27, 17, 7, 6, 86, 76, 66, 56, 46, 36, 26, 16, 6, 5, 85, 75, 65, 55, 45, 35, 25, 15, 5, 4, 84, 74, 64, 54, 44, 34, 24, 14, 4, 3, 83, 73, 63, 53, 43, 33, 23, 13, 3, 2
OFFSET
0,1
LINKS
FORMULA
a(n) = A061601(A004086(n)). - Indranil Ghosh, Jan 30 2017
EXAMPLE
a(17) = 28. Digit reversal of 17 = 71, 9's complement of 71 is 99-71 = 28.
MAPLE
R := proc(n) local nn, nnn: nn:=convert(n, base, 10): add(nn[nops(nn)+1-j]*10^(j-1), j=1..nops(nn)): end:
A109910 := proc(n) return 10^length(max(R(n), 1)) - R(n) - 1: end:
seq(A109910(n), n=0..70); # Nathaniel Johnston, Apr 28 2011
MATHEMATICA
Table[10^If[# == 0, 1, IntegerLength@ #] - 1 - # &@ FromDigits@ Reverse@ IntegerDigits@ n, {n, 0, 70}] (* Michael De Vlieger, Feb 01 2017 *)
PROG
(Python)
def A109910(n):
....x=int(str(n)[::-1])
....return 10**len(str(x))-1-x # Indranil Ghosh, Jan 30 2017
CROSSREFS
KEYWORD
base,easy,nonn,look
AUTHOR
Amarnath Murthy, Jul 16 2005
STATUS
approved