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%I #9 Jul 20 2024 15:07:51
%S 1,15,4095,66066
%N Positive integers that can be written as a Stirling number of the second kind in more than one way.
%C k*(k+1)/2 is a term if k is a term of A215797 and k != 0,2.
%C a(5) > 10^8 (if it exists).
%e With S2(n,k) = A008277(n,k):
%e 1 = S2( 1, 1) = S2( 2, 1) (for example);
%e 15 = S2( 5, 2) = S2( 6, 5);
%e 4095 = S2(13, 2) = S2( 91, 90);
%e 66066 = S2(14,11) = S2(364,363).
%Y Cf. A008277, A024412, A215797.
%K nonn,more
%O 1,2
%A _Pontus von Brömssen_, Jul 20 2024