A377228 Repdigits which are also Harshad numbers.

1, 2, 3, 4, 5, 6, 7, 8, 9, 111, 222, 333, 444, 555, 666, 777, 888, 999, 111111111, 222222222, 333333333, 444444444, 555555555, 666666666, 777777777, 888888888, 999999999, 111111111111111111111111111, 222222222222222222222222222, 333333333333333333333333333, 444444444444444444444444444

Offset

1,2

Links

Table of n, a(n) for n=1..31.

Example

999 is in the sequence as it is a repdigit (all digits are equal (in base 10)) and 999 is divisible by its sum of digits; 9 + 9 + 9 = 27 is a divisors of 999. - David A. Corneth, Oct 20 2024

Mathematica

Select[Union[FromDigits/@Flatten[Table[PadRight[{}, i, n], {n, 9}, {i, 27}], 1]], Divisible[#, DigitSum[#]]&] (* James C. McMahon, Jan 07 2025 *)

Prog

(PARI) repd(n) = 10^((n+8)\9)\9*((n-1)%9+1); \\ A010785
lista(nn) = select(x->(x%sumdigits(x)==0), vector(nn, k, repd(k))); \\ Michel Marcus, Jan 07 2025

Crossrefs

Intersection of A005349 and A010785.

Cf. A014950.

Sequence in context: A283868 A087995 A082232 * A117228 A032567 A134853

Adjacent sequences: A377225 A377226 A377227 * A377229 A377230 A377231

Keyword

nonn,base

Author

John Bibby, Oct 20 2024

Extensions

More terms from David A. Corneth, Oct 20 2024

Status

approved