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A297933
Rectangular array, by antidiagonals: Row n gives the numbers whose base-2 digits d(m), d(m-1), ..., d(0) having n as maximal run-length of 1's.
3
1, 2, 3, 4, 6, 7, 5, 11, 14, 15, 8, 12, 23, 30, 31, 9, 13, 28, 47, 62, 63, 10, 19, 29, 60, 95, 126, 127, 16, 22, 39, 61, 124, 191, 254, 255, 17, 24, 46, 79, 125, 252, 383, 510, 511, 18, 25, 55, 94, 159, 253, 508, 767, 1022, 1023, 20, 26, 56, 111, 190, 319
OFFSET
1,2
COMMENTS
Every positive integer occurs exactly once, so that as a sequence, this is a permutation of the positive integers.
EXAMPLE
Northwest corner:
1 2 4 5 8 9 10 16
3 6 11 12 13 19 22 24
7 14 23 28 29 39 46 55
15 30 47 60 61 79 94 111
31 62 95 124 125 159 190 223
63 126 191 252 253 319 382 447
127 254 383 508 509 639 766 895
***
Base-2 digits of 59: 1,1,1,0,1,1 with runs 111 and 11 of 1's, so that 59 is in row 3.
MATHEMATICA
b = 2; s[n_] := Split[IntegerDigits[n, b]];
m[n_, d_] := Union[Select[s[n], MemberQ[#, d] &]]
h[n_, d_] := Max[Map[Length, m[n, d]]]
z = 6000; w = t[d_] := Table[h[n, d], {n, 1, z}] /. -Infinity -> 0
TableForm[Table[Flatten[Position[t[1], d]], {d, 0, 8}]] (* A297933 array *)
u[d_] := Flatten[Position[t[1], d]]
v[d_, n_] := u[d][[n]];
Table[v[n, k - n + 1], {k, 1, 11}, {n, 1, k}] // Flatten (* A297933 sequence *)
CROSSREFS
Sequence in context: A048201 A186004 A056534 * A360646 A130264 A072659
KEYWORD
nonn,base,easy,tabl
AUTHOR
Clark Kimberling, Jan 26 2018
STATUS
approved