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A167810
Number of admissible basis in the postage stamp problem for n denominations and h = 3 stamps.
6
1, 3, 13, 86, 760, 8518, 116278, 1911198, 37063964, 835779524, 21626042510, 635611172160, 21033034941826, 777710150809009
OFFSET
1,2
COMMENTS
A basis 1 = b_1 < b_2 ... < b_n is admissible if all the values 1 <= x <= b_n is obtainable as a sum of at most h (not necessarily distinct) numbers in the basis.
REFERENCES
R. K. Guy, Unsolved Problems in Number Theory, C12.
LINKS
R. Alter and J. A. Barnett, A postage stamp problem, Amer. Math. Monthly, 87 (1980), 206-210.
M. F. Challis, Two new techniques for computing extremal h-bases A_k, Comp J 36(2) (1993) 117-126
Erich Friedman, Postage stamp problem
W. F. Lunnon, A postage stamp problem, Comput. J. 12 (1969) 377-380.
CROSSREFS
Other enumerations with different parameters: A167809 (h = 2), A167810 (h = 3), A167811 (h = 4), A167812 (h = 5), A167813 (h = 6), A167814 (h = 7).
For h = 2, cf. A008932.
A152112 is essentially the same sequence by definition. [From Herbert Kociemba, Jul 14 2010]
Sequence in context: A157451 A188204 A152112 * A331646 A054420 A363656
KEYWORD
hard,more,nonn
AUTHOR
Yogy Namara (yogy.namara(AT)gmail.com), Nov 12 2009
EXTENSIONS
Terms a(1) to a(12) verified and new terms a(13) and a(14) added by Herbert Kociemba, Jul 14 2010
STATUS
approved