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%I #5 Oct 09 2023 18:48:07
%S 1,2,3,4,5,6,0,21,22,23,24,25,26,20,31,32,33,34,35,36,30,41,42,43,44,
%T 45,46,40,51,52,53,54,55,56,50,61,62,63,64,65,66,60,1,2,3,4,5,6,0,211,
%U 212,213,214,215,216,210,221,222,223,224
%N Apply the transformation 0 -> 1 -> 2 -> 3 -> 4 -> 5 -> 6 -> 0 to the digits of n written in base 7; do not convert back to base 10.
%C Base 7 variant of A256078 (base 2) and A048379 (base 10). See A256303 - A256308 for bases 3 through 8, A256289 for base 9, and A256297 for the variant where the result is converted back to base 10.
%e a(7) = 21 because 7 = "10" (in base 7) becomes "21".
%e a(48) = 0 because 48 = "66" (in base 7) becomes "00".
%t Table[FromDigits[IntegerDigits[n,7]/.{0->1,1->2,2->3,3->4,4->5,5->6,6->0}],{n,0,60}] (* _Harvey P. Dale_, Oct 09 2023 *)
%o (PARI) A256307(n,b=7)=!n+eval(Strchr(apply(d->(d+1)%b+48, digits(n,b))))
%K nonn,base,easy
%O 0,2
%A _M. F. Hasler_, Mar 22 2015