

A101900


Column 0 of triangular matrix A101897, in which column k equals column 0 of A101897^(k+1) and where the nth row sums are zero for n>0.


4



1, 1, 1, 2, 5, 17, 71, 357, 2101, 14203, 108609, 927961, 8769087, 90874197, 1025292311, 12516360103, 164433702745, 2313858448075, 34730232119381, 553983478001961, 9359820238735507, 167004393073794933, 3138414712193291915, 61966152586833353847
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OFFSET

0,4


REFERENCES

Isak Hilmarsson, Ingibjorg Jonsdottir, Steinunn Sigurdardottir and Sigridur Vidarsdottir, Wilfclassification of mesh patterns of short length, http://skemman.is/stream/get/1946/9181/22991/4/Wilfclassification_of_mesh_patterns_of_short_length.pdf.


LINKS

Table of n, a(n) for n=0..23.


CROSSREFS

Cf. A101897, A101898, A101899, A101901.
Sequence in context: A143382 A057219 A084869 * A005966 A082282 A005967
Adjacent sequences: A101897 A101898 A101899 * A101901 A101902 A101903


KEYWORD

sign


AUTHOR

Paul D. Hanna, Dec 20 2004


STATUS

approved



