A214950 Denominator of sum of reciprocals of all nonzero digits of n in decimal representation.

1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 2, 2, 1, 6, 4, 10, 3, 14, 8, 18, 3, 3, 6, 3, 12, 15, 2, 21, 24, 9, 4, 4, 4, 12, 2, 20, 12, 28, 8, 36, 5, 5, 10, 15, 20, 5, 30, 35, 40, 45, 6, 6, 3, 2, 12, 30, 3, 42, 24, 18, 7, 7, 14, 21, 28, 35, 42

Offset

0,3

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Formula

a(A034708(n)) = a(A037268(n)) = a(A214957(n)) = a(A214959(n)) = 1;

a(n) = a(A004719(n)).

Mathematica

dsr[n_] := Denominator[Total[1/Select[IntegerDigits[n], # > 0 &]]]; dsr /@ Range[0, 76] (* Jayanta Basu, Jul 13 2013 *)

Prog

(Haskell)
import Data.Ratio ((%), denominator)
a214950 = f 0 where
   f y 0 = denominator y
   f y x = f (y + if d == 0 then 0 else 1 % d) x'
           where (x', d) = divMod x 10
(PARI) a(n) = my(d=digits(n)); denominator(sum(k=1, #d, if (d[k], 1/d[k]))); \\ Michel Marcus, Jan 26 2022

Crossrefs

Cf. A034708, A037268, A214957, A214959, A004719.

Cf. A214949 (numerators).

Sequence in context: A113230 A065881 A133048 * A054055 A067456 A052429

Adjacent sequences: A214947 A214948 A214949 * A214951 A214952 A214953

Keyword

nonn,base,frac

Author

Reinhard Zumkeller, Aug 02 2012

Status

approved