A143473 Replace the leading digit d of n with 10-d (in decimal representation).

10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 30, 31

Offset

0,1

Comments

a(n) = n iff A000030(n) = 5, cf. A217398.

Links

R. Zumkeller, Table of n, a(n) for n = 0..9999

Formula

A000030(a(n)) = 10 - A000030(n).

Mathematica

ld10[n_]:=Module[{idn=IntegerDigits[n]}, FromDigits[Join[{10-idn[[1]]}, Rest[ idn]]]]; Array[ld10, 100, 0] (* Harvey P. Dale, May 25 2020 *)

Prog

(Haskell)
a143473 n = foldl (\v d -> 10 * v + d) 0 $ (10 - z) : zs where
   (z:zs) = map (read . return) $ show n

Crossrefs

Sequence in context: A052036 A304622 A178914 * A055121 A249591 A132674

Adjacent sequences: A143470 A143471 A143472 * A143474 A143475 A143476

Keyword

nonn,base,look

Author

Reinhard Zumkeller, Aug 18 2008

Status

approved