A191741 Dispersion of A047217, (numbers >1 and congruent to 0 or 1 or 2 mod 5), by antidiagonals.
1, 2, 3, 5, 6, 4, 10, 11, 7, 8, 17, 20, 12, 15, 9, 30, 35, 21, 26, 16, 13, 51, 60, 36, 45, 27, 22, 14, 86, 101, 61, 76, 46, 37, 25, 18, 145, 170, 102, 127, 77, 62, 42, 31, 19, 242, 285, 171, 212, 130, 105, 71, 52, 32, 23, 405, 476, 286, 355, 217, 176, 120
Offset: 1
Examples
Northwest corner: 1....2....5....10...17 3....6....11...20...35 4....7....12...21...36 8....15...26...45...76 9....16...27...46...77 13...22...37...62...105
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=5; c2=6; 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}] (* A047217 *) 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}]] (* A191741 *) Flatten[Table[t[k, n - k + 1], {n, 1, c1}, {k, 1, n}]] (* A191741 *)
Comments