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A037864 a(n)=(number of digits <=2)-(number of digits >2) in base 5 representation of n.

%I A037864 #12 Jan 27 2025 07:32:23
%S A037864 1,1,-1,-1,2,2,2,0,0,2,2,2,0,0,0,0,0,-2,-2,0,0,0,-2,-2,3,3,3,1,1,3,3,
%T A037864 3,1,1,3,3,3,1,1,1,1,1,-1,-1,1,1,1,-1,-1,3,3,3,1,1,3,3,3,1,1,3,3,3,1,
%U A037864 1,1,1,1,-1,-1,1,1,1,-1,-1,1,1,1,-1,-1,1,1,1
%N A037864 a(n)=(number of digits <=2)-(number of digits >2) in base 5 representation of n.
%p A037864 A037864 := proc(n)
%p A037864     a := 0 ;
%p A037864     dgs := convert(n,base,5);
%p A037864     for i from 1 to nops(dgs) do
%p A037864         if op(i,dgs)<=2 then
%p A037864             a := a+1 ;
%p A037864         else
%p A037864             a := a-1 ;
%p A037864         end if;
%p A037864     end do:
%p A037864     a ;
%p A037864 end proc: # _R. J. Mathar_, Oct 16 2015
%t A037864 nd5[n_]:=Module[{idn5=IntegerDigits[n,5],a},a=Count[idn5,_?(#<=2&)];2a-Length[idn5]]; Array[nd5,90] (* _Harvey P. Dale_, Oct 13 2011 *)
%Y A037864 Cf. A110592.
%K A037864 base,sign
%O A037864 1,5
%A A037864 _Clark Kimberling_