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%I #7 Sep 30 2017 04:46:30
%S 0,0,0,26,47,188,245,343,494,821,901,1283,1729,1972,2715,3795,4030,
%T 4788,5681,6379,6948,9484,9913,10342,10771,14064,15035,19182,19865,
%U 20548,27315,28194,29073,29952,33351,34302,35253,50772,52106,53440,54774
%N Largest number that is not the sum of five n-gonal numbers.
%C Legendre proved that a number N is the sum of five n-gonal numbers if N >= 28(n-2)^3. For odd n, four n-gonal numbers are enough. See A118368.
%D Melvyn B. Nathanson, Additive number theory: the classical bases, Springer, 1996.
%H R. K. Guy, <a href="http://www.jstor.org/stable/2324367">Every number is expressible as the sum of how many polygonal numbers?</a>, Amer. Math. Monthly 101 (1994), 169-172.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PolygonalNumber.html">Polygonal Number</a>
%Y Cf. A118368.
%K nonn
%O 3,4
%A _T. D. Noe_, Apr 25 2006