A217928 Sum of distinct decimal digits appearing in n.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 1, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 2, 5, 6, 7, 8, 9, 10, 11, 3, 4, 5, 3, 7, 8, 9, 10, 11, 12, 4, 5, 6, 7, 4, 9, 10, 11, 12, 13, 5, 6, 7, 8, 9, 5, 11, 12, 13, 14, 6, 7, 8, 9, 10, 11, 6, 13, 14, 15, 7, 8, 9, 10, 11, 12, 13, 7, 15, 16, 8, 9, 10, 11, 12, 13, 14, 15, 8, 17, 9, 10, 11, 12, 13, 14, 15, 16, 17, 9, 1

Offset: 0

Author

Max Alekseyev, Oct 15 2012

Keywords

• base
• easy
• nonn

Comments

a(n) <= 45 = 1+2+3+4+5+6+7+8+9; A227378(n) = smallest number m such that a(m) = n, 0 <= n <= 45. - Reinhard Zumkeller, Jul 09 2013

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 0..10000
• Index entries for Colombian or self numbers and related sequences

Crossrefs

Cf. A007953, A180410.

Programs

Haskell

import Data.List (nub)
a217928 = sum . nub . map (read . return) . show :: Integer -> Integer
-- Reinhard Zumkeller, Jul 09 2013

Maple

a:= n-> add(i, i={convert(n, base, 10)[]}):
seq(a(n), n=0..100);  # Alois P. Heinz, Sep 21 2022

PARI

{ a(n) = local( d = vecsort( eval(Vec(Str(n))),,8) ); sum(i=1,#d,d[i]) }

PARI

a(n) = vecsum(Set(digits(n))); \\ Michel Marcus, Sep 13 2022

Python

def a(n): return sum(map(int, set(str(n))))
print([a(n) for n in range(101)]) # Michael S. Branicky, Sep 13 2022

Formula

a(n) = A007953(A180410(n)). - Michel Marcus, Sep 21 2022