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A038195 Triangle read by rows: T(n,k) (n >= 2, 0 <= k <= n) = number of over-all crude totals of unbranched k-5-catapolyheptagons. 0
1, 2, 1, 4, 10, 8, 2, 16, 48, 52, 24, 4, 64, 224, 304, 200, 64, 8, 256, 1024, 1664, 1408, 656, 160, 16, 1024, 4608, 8704, 8960, 5440, 1952, 384, 32, 4096, 20480, 44032, 53248, 39680, 18688, 5440, 896, 64, 16384, 90112, 217088, 301056, 265216, 154112, 59136, 14464, 2048, 128 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

REFERENCES

B. N. Cyvin et al., Isomer enumeration of unbranched catacondensed polygonal systems with pentagons and heptagons, Match, No. 34 (Oct 1996), pp. 109-121. See Table 1.

LINKS

Table of n, a(n) for n=2..53.

FORMULA

T(n,k) = 2^(2*n-k-2)*(binomial(n-1,k-1)+binomial(n-2,k)/4).

EXAMPLE

Triangle begins:

[1, 2, 1],

[4, 10, 8, 2],

[16, 48, 52, 24, 4],

[64, 224, 304, 200, 64, 8],

[256, 1024, 1664, 1408, 656, 160, 16],

[1024, 4608, 8704, 8960, 5440, 1952, 384, 32],

[4096, 20480, 44032, 53248, 39680, 18688, 5440, 896, 64],

[16384, 90112, 217088, 301056, 265216, 154112, 59136, 14464, 2048, 128],

...

CROSSREFS

Sequence in context: A219002 A156919 A179077 * A212770 A205855 A038521

Adjacent sequences:  A038192 A038193 A038194 * A038196 A038197 A038198

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane.

EXTENSIONS

Revised by N. J. A. Sloane, Feb 08 2019

STATUS

approved

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Last modified October 20 16:00 EDT 2019. Contains 328267 sequences. (Running on oeis4.)