A144980 Natural numbers k such that k+1 is divisible by the sum of the decimal digits of k.

1, 10, 11, 14, 19, 31, 34, 65, 71, 79, 100, 101, 103, 104, 109, 143, 160, 164, 167, 211, 215, 223, 263, 293, 299, 337, 362, 367, 379, 412, 419, 431, 454, 458, 461, 479, 503, 545, 560, 571, 601, 655, 659, 671, 689, 764, 769, 799, 805, 839, 892, 896, 917, 922

Offset

1,2

Comments

The complement of this sequences is A178338.

The sequence is infinite since if m = 10^j then (m+1) / digitsum(m) = m. - Marius A. Burtea, Dec 21 2018

Links

Nathaniel Johnston, Table of n, a(n) for n = 1..10000

Example

1+1 = 2 is divisible by 1, hence 1 is in the sequence; 65+1 = 66 is divisible by 6+5 = 11, hence 65 is in the sequence.

Maple

A007953 := proc(n) local d; add(d, d=convert(n, base, 10)) ; end: isA144980 := proc(n) RETURN( (n+1) mod A007953(n) = 0 ) ; end: for n from 1 to 1800 do if isA144980(n) then printf("%d, ", n) ; fi; od: # R. J. Mathar, Sep 30 2008

Mathematica

Select[Range[2000], Mod[#+1, Total[IntegerDigits[#]]]==0&] (* Harvey P. Dale, Nov 13 2010 *)

Prog

(Magma) [n: n in [1..2000]|IsIntegral((n+1)/&+Intseq(n))]; // Marius A. Burtea, Dec 18 2018

Crossrefs

Cf. A144967.

Cf. A005349. - R. J. Mathar, Sep 30 2008

Sequence in context: A335237 A214864 A062844 * A261713 A244283 A043583

Adjacent sequences: A144977 A144978 A144979 * A144981 A144982 A144983

Keyword

nonn,base,easy

Author

Giovanni Teofilatto, Sep 28 2008

Extensions

a(1) inserted, extended beyond a(7). Example added, cross-reference added. Keyword base added, keyword more deleted, offset changed from 1,1 to 1,2. - Klaus Brockhaus, Sep 30 2008

Extended by R. J. Mathar, Sep 30 2008

Status

approved