A380642 Numbers k such that the total number of digits d in the numbers from 1 to k is even for each d from 0 to 9.

0, 122, 220, 440, 660, 880, 10022, 10100, 10198, 10202, 10918, 11000, 11098, 11122, 11220, 11440, 11660, 11880, 12002, 12120, 12222, 12344, 12442, 12662, 12882, 13244, 13322, 13424, 14140, 14242, 14324, 14422, 15522, 16160, 16262, 16622, 17722, 18180, 18282, 18822, 19018, 19922

Offset

1,2

Links

Paolo Xausa, Table of n, a(n) for n = 1..10000

Mathematica

Join[{0}, Module[{d = 0}, Table[If[AllTrue[EvenQ[d += DigitCount[k]], TrueQ], k, Nothing], {k, 20000}]]] (* Paolo Xausa, Jan 29 2025 *)

Prog

(PARI) D = vector(10); for(n=1, oo, foreach(digits(n), d, D[d+1]++); D%=2; if(!vecmax(D), print1(n, ", ")) );

Crossrefs

Cf. A360320.

Sequence in context: A356369 A099154 A304605 * A158131 A004925 A369598

Adjacent sequences: A380639 A380640 A380641 * A380643 A380644 A380645

Keyword

base,nonn

Author

Max Alekseyev, Jan 28 2025

Status

approved