A257056 Numbers k such that (# squares) < (# nonsquares) in the quarter-squares representation of k.
2, 6, 8, 12, 14, 15, 20, 22, 23, 30, 32, 33, 42, 44, 45, 48, 56, 58, 59, 62, 63, 72, 74, 75, 78, 79, 80, 89, 90, 92, 93, 96, 97, 98, 108, 110, 112, 113, 116, 117, 118, 129, 132, 134, 135, 138, 139, 140, 143, 152, 156, 158, 159, 162, 163, 164, 167, 168, 177
Offset: 1
Examples
Quarter-square representations: r(0) = 0 r(1) = 1 r(2) = 2, so that a(1) = 2 r(3) = 2 + 1 r(4) = 4 r(5) = 4 + 1 r(6) = 6, so that a(2) = 6
Links
- Clark Kimberling, Table of n, a(n) for n = 1..1000
Programs
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Mathematica
z = 400; b[n_] := Floor[(n + 1)^2/4]; bb = Table[b[n], {n, 0, 100}]; s[n_] := Table[b[n], {k, b[n + 1] - b[n]}]; h[1] = {1}; h[n_] := Join[h[n - 1], s[n]]; g = h[100]; r[0] = {0}; r[n_] := If[MemberQ[bb, n], {n}, Join[{g[[n]]}, r[n - g[[n]]]]]; u = Table[Length[r[n]], {n, 0, z}] (* A257023 *) v = Table[Length[Intersection[r[n], Table[n^2, {n, 0, 1000}]]], {n, 0, z}] (* A257024 *) -1 + Select[Range[0, z], 2 v[[#]] < u[[#]] &] (* A257056 *) -1 + Select[Range[0, z], 2 v[[#]] == u[[#]] &] (* A257057 *) -1 + Select[Range[0, z], 2 v[[#]] > u[[#]] &] (* A257058 *)
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