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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A211017 T(n,k) = total area of all squares and rectangles of area 2^(k-1) after 2^n stages in the toothpick structure of A139250, n>=1, k>=1, assuming the toothpicks have length 2. Triangle read by rows.

Original entry on oeis.org

0, 0, 8, 8, 24, 16, 40, 104, 48, 32, 168, 424, 208, 96, 64, 680, 1704, 848, 416, 192, 128, 2728, 6824, 3408, 1696, 832, 384, 256, 10920, 27304, 13648, 6816, 3392, 1664, 768, 512, 43688, 109924, 54608, 27296, 13632, 6784, 3328, 1536, 1024
Offset: 1

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Author

Omar E. Pol, Sep 21 2012

Keywords

Comments

All internal regions in the toothpick structure are squares and rectangles. The area of every internal region is a power of 2.

Examples

			For n = 5 in the toothpick structure after 2^5 stages we have that:
T(5,1) = 168 is the total area of all squares of size 1 X 1.
T(5,2) = 424 is the total area of all rectangles of size 1 X 2.
T(5,3) = 208 is the total area of all squares of size 2 X 2 and of all rectangles of size 1 X 4.
T(5,4) = 96 is the total area of all rectangles of size 2 X 4.
T(5,5) = 64 is the total area of all rectangles of size 2 X 8.
Triangle begins:
      0;
      0,     8;
      8,    24,    16;
     40,   104,    48,   32;
    168,   424,   208,   96,   64;
    680,  1704,   848,  416,  192,  128;
   2728,  6824,  3408, 1696,  832,  384, 256;
  10920, 27304, 13648, 6816, 3392, 1664, 768, 512;
		

Crossrefs

Formula

T(n,k) = A211016(n,k)*2^(k-1).
T(n,1) = 4*A020988(n-2), n>=2.