A191737 Dispersion of A047212, (numbers >1 and congruent to 0 or 2 or 4 mod 5), by antidiagonals.
1, 2, 3, 4, 5, 6, 7, 9, 10, 8, 12, 15, 17, 14, 11, 20, 25, 29, 24, 19, 13, 34, 42, 49, 40, 32, 22, 16, 57, 70, 82, 67, 54, 37, 27, 18, 95, 117, 137, 112, 90, 62, 45, 30, 21, 159, 195, 229, 187, 150, 104, 75, 50, 35, 23, 265, 325, 382, 312, 250, 174, 125, 84
Offset: 1
Examples
Northwest corner: 1....2....4....7...12 3....5....9...15...25 6....10....17...29...49 8....14...24...40...67 11...19...32...54...90 13...22...37...62...104
Links
- Ivan Neretin, Table of n, a(n) for n = 1..5050 (first 100 antidiagonals, flattened)
Programs
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Mathematica
(* Program generates the dispersion array t of the increasing sequence f[n] *) r = 40; r1 = 12; c = 40; c1 = 12; a=2; b=4; c2=5; m[n_]:=If[Mod[n,3]==0,1,0]; f[n_]:=a*m[n+2]+b*m[n+1]+c2*m[n]+5*Floor[(n-1)/3] Table[f[n], {n, 1, 30}] (* A047212 *) mex[list_] := NestWhile[#1 + 1 &, 1, Union[list][[#1]] <= #1 &, 1, Length[Union[list]]] rows = {NestList[f, 1, c]}; Do[rows = Append[rows, NestList[f, mex[Flatten[rows]], r]], {r}]; t[i_, j_] := rows[[i, j]]; TableForm[Table[t[i, j], {i, 1, 10}, {j, 1, 10}]] (* A191737 *) Flatten[Table[t[k, n - k + 1], {n, 1, c1}, {k, 1, n}]] (* A191737 *)
Comments