A340228 a(n) is the sum of the lengths of all the segments used to draw a rectangle of height 2^(n-1) and width n divided into 2^(n-1) rectangles of unit height, in turn, divided into rectangles of unit height and lengths corresponding to the parts of the compositions of n.
4, 11, 27, 64, 149, 342, 775, 1736, 3849, 8458, 18443, 39948, 86029, 184334, 393231, 835600, 1769489, 3735570, 7864339, 16515092, 34603029, 72351766, 150994967, 314572824, 654311449, 1358954522, 2818572315, 5838471196, 12079595549, 24964497438, 51539607583, 106300440608
Offset: 1
Examples
Illustrations for n = 1..4:
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a(1) = 4 a(2) = 11
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a(3) = 27 a(4) = 64
Links
Crossrefs
Programs
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Mathematica
LinearRecurrence[{6,-13,12,-4},{4,11,27,64},32]