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Number of ways of obtaining a weight of n grams with a two-pan balance using eight weights of denominations 1, 1, 2, 5, 10, 10, 20 and 50 grams.
1

%I #26 Jan 03 2013 13:00:41

%S 25,30,40,50,45,50,45,50,40,30,25,31,42,54,49,55,50,56,46,35,30,36,48,

%T 60,54,60,54,60,48,36,30,35,46,56,50,55,49,54,42,31,25,30,40,50,45,50,

%U 45,50,40,30,25,29,38,46,41,45,40,44,34,25,20,24,32,40,36,40,36,40,32,24,20,22,28,32,28,30,26,28,20,14,10,11,14,16,14,15,13,14,10,7,5,5,6,6,5,5,4,4,2,1

%N Number of ways of obtaining a weight of n grams with a two-pan balance using eight weights of denominations 1, 1, 2, 5, 10, 10, 20 and 50 grams.

%D G. Pólya and G. Szegő, Problems and Theorems in Analysis, Springer-Verlag, NY, 2 vols., 1972, Vol. 1, p. 2, Problems 6 and 8.

%H <a href="/index/Mag#change">Index entries for sequences related to making change.</a>

%F G.f.: (1/x+1+x)^2*(1/x^2+1+x^2)*(1/x^5+1+x^5)*(1/x^10+1+x^10)^2*(1/x^20+1+x^20)*(1/x^50+1+x^50) (then discard terms involving negative exponents).

%F a(n) = 0 for n > 99.

%Y Cf. A214774.

%K nonn

%O 0,1

%A _N. J. A. Sloane_, Jul 28 2012