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%I #22 Dec 12 2020 04:55:22
%S 7,20,31,42,64,75,86,108,110,121,132,143,154,165,176,187,198,209,211,
%T 222,244,255,266,288,299,310,312,323,334,345,356,378,400,411,413,424,
%U 435,446,468,490,501,512,514,525,536,558,580,591,602,615,626,637,648,670,681,692
%N Numbers that are both Colombian and Brazilian.
%C 121 is the only square of prime in this sequence.
%H Wikipédia, <a href="https://fr.wikipedia.org/wiki/Nombre_br%C3%A9silien">Nombre brésilien</a> (in French).
%H <a href="/index/Br#Brazilian_numbers">Index entries for sequences related to Brazilian Numbers</a>.
%H <a href="/index/Coi#Colombian">Index entries for sequences related to Colombian Numbers</a>.
%e 20 is a term because it is not of the form m + sum of digits of m for any m < 20, so 20 is Colombian and 20 = (22)_9, so 20 is also Brazilian.
%t brazQ[n_] := Module[{b = 2, found = False}, While[b < n - 1 && Length[Union[IntegerDigits[n, b]]] > 1, b++]; b < n - 1]; n = 700; Select[Complement[Range[n], Union @ Table[Plus @@ IntegerDigits[k] + k, {k, 1, n}]], brazQ] (* _Amiram Eldar_, Apr 08 2020 after _T. D. Noe_ at A125134 *)
%Y Intersection of A003052 and A125134.
%K nonn,base
%O 1,1
%A _Bernard Schott_, Apr 08 2020
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