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%I M2125 N0842 #11 Oct 14 2023 22:33:14
%S 2,20,402,14440,825502,69055260,7960285802,1209873973712
%N Some special numbers.
%D A. Fletcher, J. C. P. Miller, L. Rosenhead and L. J. Comrie, An Index of Mathematical Tables. Vols. 1 and 2, 2nd ed., Blackwell, Oxford and Addison-Wesley, Reading, MA, 1962, Vol. 1, p. 77.
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%K nonn,more
%O 0,1
%A _N. J. A. Sloane_