

A109436


Triangle of numbers: row n gives the elements along the subdiagonal of A109435 that connects 2^n with (n+2)*2^(n1).


2



0, 0, 1, 1, 2, 3, 4, 7, 8, 8, 15, 19, 20, 16, 31, 43, 47, 48, 32, 63, 94, 107, 111, 112, 64, 127, 201, 238, 251, 255, 256, 128, 255, 423, 520, 558, 571, 575, 576, 256, 511, 880, 1121, 1224, 1262, 1275, 1279, 1280, 512, 1023, 1815, 2391, 2656, 2760, 2798, 2811
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OFFSET

0,5


COMMENTS

In the limit of row number n>infinity, the differences of the nth row of the table, read from right to left, are 1, 4, 13, 38, 104,... = A084851.


LINKS

Table of n, a(n) for n=0..55.


EXAMPLE

The triangle A109435 begins
1;
2, 1;
4, 3, 1;
8, 7, 3, 1;
16, 15, 8, 3, 1;
32, 31, 19, 8, 3, 1;
64, 63, 43, 20, 8, 3, 1;
128, 127, 94, 47, 20, 8, 3, 1;
If we read this triangle starting at 2^n in its first column along its nth subdiagonal up to the first occurrence of (n+2)*2^(n1), we get row n of the current triangle, which begins:
0, 0;
1, 1;
2, 3;
4, 7, 8;
8, 15, 19, 20;
16, 31, 43, 47, 48;
32, 63, 94, 107, 111, 112;


MATHEMATICA

T[n_, m_] := Length[ Select[ StringPosition[ #, StringDrop[ ToString[10^m], 1]] & /@ Table[ ToString[ FromDigits[ IntegerDigits[i, 2]]], {i, 2^n, 2^(n + 1)  1}], # != {} &]]; Flatten[ Table[ T[n + i, i], {n, 0, 9}, {i, 0, n}]]


CROSSREFS

Cf. A109435, A001792, A109434, A084851.
Sequence in context: A054424 A297164 A207800 * A177045 A241783 A039254
Adjacent sequences: A109433 A109434 A109435 * A109437 A109438 A109439


KEYWORD

base,nonn,tabf


AUTHOR

Robert G. Wilson v, Jun 28 2005


EXTENSIONS

Edited by R. J. Mathar, Nov 17 2009


STATUS

approved



