%I #7 Jun 28 2022 18:36:17
%S 1,1,1,-1,-1,-1,2,2,2,2,0,0,0,2,2,2,2,0,0,0,2,2,2,2,0,0,0,0,0,0,0,-2,
%T -2,-2,0,0,0,0,-2,-2,-2,0,0,0,0,-2,-2,-2,3,3,3,3,1,1,1,3,3,3,3,1,1,1,
%U 3,3,3,3,1,1,1,3,3,3,3,1,1,1,1,1,1,1,-1,-1,-1,1
%N a(n)=(number of digits <=3)-(number of digits >3) in base 7 representation of n.
%t d37[n_]:=Module[{d=IntegerDigits[n,7]},Count[d,_?(#<4&)]-Count[d,_?(#>3&)]]; Array[d37,90,0] (* _Harvey P. Dale_, Jun 28 2022 *)
%K base,sign
%O 0,7
%A _Clark Kimberling_
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