A001216 a(n) = solution to the postage stamp problem with n denominations and 6 stamps. (Formerly M4120 N1831)

6, 18, 52, 114, 216, 388, 638, 1007, 1545, 2287

Offset

1,1

Comments

Fred Lunnon [W. F. Lunnon] defines "solution" to be the smallest value not obtainable by the best set of stamps. The solutions given are one lower than this, that is, the sequence gives the largest number obtainable without a break using the best set of stamps.

References

R. K. Guy, Unsolved Problems in Number Theory, C12.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

Table of n, a(n) for n=1..10.

R. Alter and J. A. Barnett, A postage stamp problem, Amer. Math. Monthly, 87 (1980), 206-210.

M. F. Challis and J. P. Robinson, Some Extremal Postage Stamp Bases, J. Integer Seq., 13 (2010), Article 10.2.3. [From John P Robinson (john-robinson(AT)uiowa.edu), Feb 18 2010]

Erich Friedman, Postage stamp problem

R. L. Graham and N. J. A. Sloane, On Additive Bases and Harmonious Graphs

R. L. Graham and N. J. A. Sloane, On Additive Bases and Harmonious Graphs, SIAM J. Algebraic and Discrete Methods, 1 (1980), 382-404.

W. F. Lunnon, A postage stamp problem, Comput. J. 12 (1969) 377-380.

Crossrefs

Postage stamp sequences: A001208, A001209, A001210, A001211, A001212, A001213, A001214, A001215, A001216, A005342, A005343, A005344, A014616, A053346, A053348, A075060, A084192, A084193.

A row or column of the array A196416 (possibly with 1 subtracted from it).

Sequence in context: A220227 A075650 A015645 * A318484 A079843 A290582

Adjacent sequences: A001213 A001214 A001215 * A001217 A001218 A001219

Keyword

nonn,more

Author

N. J. A. Sloane

Extensions

Entry improved by comments from John Seldon (johnseldon(AT)onetel.com), Sep 15 2004

Added terms a(8) and a(9) from Challis and Robinson. John P Robinson (john-robinson(AT)uiowa.edu), Feb 18 2010

a(10) from Friedman by Robert Price, Jul 19 2013

Status

approved