A370893 Rectangular array, read by antidiagonals: row n consists of the numbers m whose ternary representation has exactly n runs.
1, 2, 3, 4, 5, 10, 8, 6, 11, 30, 13, 7, 15, 32, 91, 26, 9, 16, 33, 92, 273, 40, 12, 19, 34, 96, 275, 820, 80, 14, 20, 46, 97, 276, 821, 2460, 121, 17, 21, 47, 100, 277, 825, 2462, 7381, 242, 18, 23, 48, 101, 289, 826, 2463, 7382, 22143
Offset: 1
Examples
Corner:
1 2 4 8 13 26 40
3 5 6 7 9 12 14
10 11 15 16 19 20 21
30 32 33 34 46 47 48
91 92 96 97 100 101 102
273 275 276 277 289 290 291
820 821 825 826 829 830 831
2460 2462 2463 2464 2476 2477 2478
The ternary representation of 12 is 110, which has 2 runs: 11 and 0.
Programs
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Mathematica
a[n_] := a[n] = Select[Range[25000], Length[Split[IntegerDigits[#, 3]]] == n &]; t[n_, k_] := a[n][[k]]; Grid[Table[t[n, k], {n, 1, 10}, {k, 1, 10}]] (* array *) Table[t[n - k + 1, k], {n, 10}, {k, n, 1, -1}] // Flatten (* sequence *)
Comments