A332046 a(n) is the smallest positive integer such that there exist exactly n positive integers less than a(n) whose digital sum in base 10 is equal to the digital sum of a(n).

10, 20, 30, 40, 50, 60, 70, 80, 90, 108, 117, 126, 135, 144, 153, 162, 171, 180, 207, 216, 225, 234, 243, 252, 261, 270, 280, 307, 316, 325, 334, 343, 352, 361, 370, 406, 415, 424, 433, 442, 451, 460, 470, 506, 515, 524, 533, 542, 551, 560, 605, 614, 623, 632, 641, 650, 660

Offset

1,1

Links

Table of n, a(n) for n=1..57.

Example

For n=10, 108 is the smallest positive integer for which there exists exactly 10 smaller integers whose digit sum in base 10 is the same as the digit sum of 108 (i.e., 1+0+8=9). These integers are 9, 18, 27, 36, 45, 54, 63, 72, 81, 90.

Prog

(PARI) isok(k, n) = {my(v=vector(k, j, sumdigits(j))); #select(x->(x==v[k]), v) == n+1; }
a(n) = {my(k=1); while(! isok(k, n), k++); k; } \\ Michel Marcus, Feb 16 2020

Crossrefs

Cf. A081926 (similar but different definition).

Sequence in context: A043489 A352438 A028440 * A166511 A062237 A162467

Adjacent sequences: A332043 A332044 A332045 * A332047 A332048 A332049

Keyword

nonn,base

Author

Arnauld Chevallier, Feb 06 2020

Status

approved