A327264 Numbers k with digit_sum(2*k) = digit_sum(2+k).

2, 11, 20, 47, 74, 83, 92, 101, 110, 137, 146, 164, 173, 182, 191, 200, 227, 236, 245, 254, 263, 272, 281, 290, 317, 326, 335, 353, 362, 371, 380, 407, 416, 425, 452, 461, 470, 497, 524, 533, 542, 569, 578, 614, 623, 632, 641, 659, 668

Offset: 1

Author

Max Lacoma, Sep 14 2019

Keywords

• nonn
• look
• base

Comments

The graph is fairly interesting, as the terms are clustered together linearly in different sections.

The sequence is infinite since it contains all the terms 2*10^k, for k >= 0. - Metin Sariyar, Sep 16 2019

Links

• Max Lacoma, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A007953.

Programs

Mathematica

Select[Range@700, Equal @@ Plus @@@ IntegerDigits[{2 #, 2 + #}] &] (* Giovanni Resta, Sep 16 2019 *)

PARI

isok(k) = sumdigits(2*k) == sumdigits(k+2); \\ Michel Marcus, Sep 16 2019