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%I #11 Aug 26 2023 19:00:48
%S 1,15,36,45,325,561,1225,1540,3025,4186,11781,40755,41041,58311,
%T 121771,221445,1334161,1413721,1777555,3000025,5785101,27169506,
%U 36855405,113123361,321197185,1167483681,1533776805,1631432881
%N Numbers that are n-gons for three or more n's, where n=3,4,5,...,16.
%D Albert H. Beiler, Recreations in the Theory of Numbers: The Queen of Mathematics Entertains 185-99 (2d ed. 1966)
%H Donovan Johnson, <a href="/A062712/b062712.txt">Table of n, a(n) for n = 1..58</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PolygonalNumber.html">Polygonal Number</a>
%e 45 is a triangular, hexagonal and hexadecagonal number
%t Select[Tally[Flatten[Table[PolygonalNumber[b,Range[10^6]],{b,3,16}]]],#[[2]]>2&][[;;,1]]//Union (* _Harvey P. Dale_, Aug 26 2023 *)
%K nonn
%O 1,2
%A _Harvey P. Dale_, Jul 14 2001
%E More terms from _Eric W. Weisstein_, Nov 30, 2003.
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