cp's OEIS Frontend

A001215 a(n) is the solution to the postage stamp problem with n denominations and 5 stamps.

%I A001215 M3845 N1706 #44 Feb 03 2022 02:27:42
%S A001215 5,14,35,71,126,211,336,524,726,1016,1393,1871,2494,3196,4063,5113,
%T A001215 6511,7949,9865,11589
%N A001215 a(n) is the solution to the postage stamp problem with n denominations and 5 stamps.
%C A001215 _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.
%D A001215 R. K. Guy, Unsolved Problems in Number Theory, C12.
%D A001215 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D A001215 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A001215 R. Alter and J. A. Barnett, <a href="http://www.jstor.org/stable/2321610">A postage stamp problem</a>, Amer. Math. Monthly, 87 (1980), 206-210.
%H A001215 M. F. Challis, <a href="http://dx.doi.org/10.1093/comjnl/36.2.117">Two new techniques for computing extremal h-bases A_k</a>, Comp. J. 36(2) (1993) 117-126
%H A001215 M. F. Challis and J. P. Robinson, <a href="http://www.cs.uwaterloo.ca/journals/JIS/VOL13/Challis/challis6.html">Some Extremal Postage Stamp Bases</a>, J. Integer Seq., 13 (2010), Article 10.2.3.
%H A001215 Erich Friedman, <a href="https://erich-friedman.github.io/mathmagic/0403.html">Postage stamp problem</a>
%H A001215 R. L. Graham and N. J. A. Sloane, <a href="http://neilsloane.com/doc/RLG/073.pdf">On Additive Bases and Harmonious Graphs</a>
%H A001215 R. L. Graham and N. J. A. Sloane, <a href="http://dx.doi.org/10.1137/0601045">On Additive Bases and Harmonious Graphs</a>, SIAM J. Algebraic and Discrete Methods, 1 (1980), 382-404.
%H A001215 W. F. Lunnon, <a href="https://doi.org/10.1093/comjnl/12.4.377">A postage stamp problem</a>, Comput. J. 12 (1969) 377-380.
%Y A001215 Postage stamp sequences: A001208, A001209, A001210, A001211, A001212, A001213, A001214, A001215, A001216, A005342, A005343, A005344, A014616, A053346, A053348, A075060, A084192, A084193.
%Y A001215 A row or column of the array A196416 (possibly with 1 subtracted from it).
%K A001215 nonn,more
%O A001215 1,1
%A A001215 _N. J. A. Sloane_
%E A001215 a(9) from Challis added by _R. J. Mathar_, Apr 01 2006
%E A001215 Entry improved by comments from John Seldon (johnseldon(AT)onetel.com), Sep 15 2004
%E A001215 a(10) from Challis and Robinson added by John P Robinson (john-robinson(AT)uiowa.edu), Feb 18 2010
%E A001215 a(11)-a(20) from Friedman added by _Robert Price_, Jul 19 2013