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A029448
Numbers k that divide the (right) concatenation of all numbers <= k written in base 3 (most significant digit on left).
0
1, 3, 4, 9, 12, 27, 72, 81, 104, 216, 219, 243, 324, 729, 756, 972, 2187, 3888, 3921, 6561, 9477, 11664, 16848, 19683, 21156, 22599, 26244, 26811, 29245, 30132, 32805, 37665, 38788, 39852, 40905, 45756, 46965, 47871, 59049, 78732, 80676, 82380
OFFSET
1,2
MATHEMATICA
b = 3; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[c, IntegerDigits[#, b]], b], #] &] (* Robert Price, Mar 10 2020 *)
KEYWORD
nonn,base
EXTENSIONS
More terms from David W. Wilson
STATUS
approved