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Numbers whose base-6 and base-7 expansions have the same digit sum.
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%I #34 Apr 11 2023 08:45:57

%S 1,2,3,4,5,66,67,68,69,126,127,128,129,130,131,156,157,158,159,160,

%T 189,190,191,246,247,248,249,250,251,280,281,308,309,310,311,366,367,

%U 368,369,370,396,397,398,456,457,458,459,460,461,518,519,520,521,546,547

%N Numbers whose base-6 and base-7 expansions have the same digit sum.

%F {n: A053827(n) = A053828(n)}. - _R. J. Mathar_, Jun 30 2021

%o (PARI) isok(k) = sumdigits(k, 6) == sumdigits(k, 7); \\ _Michel Marcus_, Mar 18 2023

%o (Python)

%o from numpy import base_repr

%o def ok(n):

%o return sum(map(int, base_repr(n, 6))) == sum(map(int, base_repr(n, 7)))

%o print([n for n in range(1, 10**5) if ok(n)])

%o # _Christoph B. Kassir_, Apr 05 2023

%Y Cf. A053827, A053828.

%K nonn,base

%O 1,2

%A _Clark Kimberling_