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%I M4884 N2094 #18 May 19 2024 12:44:24
%S 12,10206,2148007936,149011627197265625,5157212399256236248406163456,
%T 128461788760529439274299006884487791149204,
%U 3138550867693340381917894873863110037264541113810027544576
%N Number of equivalence classes of n-valued Post functions of 2 variables under action of symmetric group S_2.
%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).
%D I. Strazdins, On the number of types of l-adic functions (in Russian), Proc. Riga Polytech. Inst. 10, No. 1 (1963), 167-186.
%H M. A. Harrison and R. G. High, <a href="https://doi.org/10.1016/S0021-9800(68)80008-0">On the cycle index of a product of permutation groups</a>, J. Combin. Theory, 4 (1968), 277-299.
%Y Cf. A003180, A001321.
%K nonn
%O 2,1
%A _N. J. A. Sloane_
%E More terms from _Vladeta Jovovic_, Aug 09 2000