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A130127 Triangle defined by A000012 * A130125, read by rows. 2
1, 1, 2, 2, 2, 4, 2, 4, 4, 8, 3, 4, 8, 8, 16, 3, 6, 8, 16, 16, 32, 4, 6, 12, 16, 32, 32, 64, 4, 8, 12, 24, 32, 64, 64, 128, 5, 8, 16, 24, 48, 64, 128, 128, 256, 5, 10, 16, 32, 48, 96, 128, 256, 256, 512, 6, 10, 20, 32, 64, 96, 192, 256, 512, 512, 1024, 6, 12, 20, 40, 64, 128, 192, 384, 512, 1024, 1024, 2048 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Row sums = A011377: (1, 3, 8, 18, 39,...). A130126 = A130125 * A000012.

LINKS

G. C. Greubel, Rows n = 1..100 of triangle, flattened

FORMULA

T(n,k) = 2^(k-1) * floor((n-k+2)/2). - G. C. Greubel, Jun 06 2019

EXAMPLE

First few rows of the triangle are:

  1;

  1, 2;

  2, 2,  4;

  2, 4,  4,  8;

  3, 4,  8,  8, 16;

  3, 6,  8, 16, 16, 32;

  4, 6, 12, 16, 32, 32, 64; ...

MATHEMATICA

Table[2^(k-1)*Floor[(n-k+2)/2], {n, 1, 12}, {k, 1, n}]//Flatten (* G. C. Greubel, Jun 06 2019 *)

PROG

(PARI) {T(n, k) = 2^(k-1)*floor((n-k+2)/2)}; \\ G. C. Greubel, Jun 06 2019

(MAGMA) [[2^(k-1)*Floor((n-k+2)/2): k in [1..n]]: n in [1..12]]; // G. C. Greubel, Jun 06 2019

(Sage) [[2^(k-1)*floor((n-k+2)/2) for k in (1..n)] for n in (1..12)] # G. C. Greubel, Jun 06 2019

CROSSREFS

Cf. A000012, A130125, A130126, A011377.

Sequence in context: A330772 A105681 A240039 * A217982 A184727 A286849

Adjacent sequences:  A130124 A130125 A130126 * A130128 A130129 A130130

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, May 11 2007

EXTENSIONS

More terms added by G. C. Greubel, Jun 06 2019

STATUS

approved

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Last modified July 8 05:33 EDT 2020. Contains 335513 sequences. (Running on oeis4.)