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A109434 Irregular triangle read by rows: row n contains the numbers from 2^n up to (n+3)*2^(n-2), inclusive, read along their common subdiagonal of A109433. 2
0, 0, 1, 1, 2, 2, 4, 5, 8, 11, 12, 16, 24, 27, 28, 32, 51, 60, 63, 64, 64, 107, 131, 140, 143, 144, 128, 222, 282, 307, 316, 319, 320, 256, 457, 601, 666, 691, 700, 703, 704, 512, 935, 1270, 1432, 1498, 1523, 1532, 1535, 1536, 1024, 1904, 2665, 3057, 3224, 3290 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Evolution of 2^n into 2^(n-2)(n+3) as exhibited by A109433.

The forward differences of the last row of the table approache A058396.

LINKS

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

EXAMPLE

Triangle begins

   0  0

   1  1

   2  2

   4  5

   8 11 12

  16 24 27 28

  32 51 60 63 64

MATHEMATICA

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

CROSSREFS

Cf. A109433, A109436.

Sequence in context: A206138 A241545 A157162 * A089299 A017910 A240734

Adjacent sequences:  A109431 A109432 A109433 * A109435 A109436 A109437

KEYWORD

base,nonn,tabf

AUTHOR

Robert G. Wilson v, Jun 28 2005

EXTENSIONS

New definition from R. J. Mathar, Nov 27 2007

STATUS

approved

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Last modified January 24 04:35 EST 2020. Contains 331183 sequences. (Running on oeis4.)