A191736 Dispersion of A047205, (numbers >1 and congruent to 0 or 3 or 4 mod 5), by antidiagonals.
1, 3, 2, 5, 4, 6, 9, 8, 10, 7, 15, 14, 18, 13, 11, 25, 24, 30, 23, 19, 12, 43, 40, 50, 39, 33, 20, 16, 73, 68, 84, 65, 55, 34, 28, 17, 123, 114, 140, 109, 93, 58, 48, 29, 21, 205, 190, 234, 183, 155, 98, 80, 49, 35, 22, 343, 318, 390, 305, 259, 164, 134, 83
Offset: 1
Examples
Northwest corner: 1....3....5....9....15 2....4....8....14...24 6....10...18...30...50 7....13...23...39...65 11...19...33...55...93 12...20...34...58...98
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=3; 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}] (* A047205 *) 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}]] (* A191736 *) Flatten[Table[t[k, n - k + 1], {n, 1, c1}, {k, 1, n}]] (* A191736 *)
Comments