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A109436 Triangle of numbers: row n gives the elements along the subdiagonal of A109435 that connects 2^n with (n+2)*2^(n-1). 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

In the limit of row number n->infinity, the differences of the n-th 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 n-th sub-diagonal up to the first occurrence of (n+2)*2^(n-1), 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

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Last modified December 11 03:29 EST 2018. Contains 318049 sequences. (Running on oeis4.)