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Number of classes of endofunctions of [n] under vertical translation mod n, complement to n+1 and reversal.
13

%I #7 Oct 01 2017 16:57:06

%S 1,1,2,4,24,169,2024,29584,525600,10764961,250030128,6484436676,

%T 185752964096,5824523694025,198428723433728,7298231591777344,

%U 288230377359679488,12165297972404595841,546477889989773968640,26031837574639154232100,1310720000002816000131072

%N Number of classes of endofunctions of [n] under vertical translation mod n, complement to n+1 and reversal.

%C There are three size of classes : n, 2n, 4n.

%C n c:n c:2n c:4n

%C ----------------------------------

%C 0 1

%C 1 1

%C 2 2

%C 3 1 2 1

%C 4 4 10 10

%C 5 1 24 144

%C 6 8 148 1868

%C 7 1 342 29241

%C For n odd, only the set of n constant functions can have a member of their class equal to their complement, so c:n size is 1.

%C For n even, we have 2^(n/2) binary words which have mirror-symmetry

%C There are three types of classes of size of 2n (stable by reversal, stable by complement, stable by rc as in A275550).

%H Andrew Howroyd, <a href="/A275553/b275553.txt">Table of n, a(n) for n = 0..100</a>

%o (PARI) \\ see A056391 for Polya enumeration functions

%o a(n) = NonequivalentSorts(ReversiblePerms(n), DihedralPerms(n)); \\ _Andrew Howroyd_, Sep 30 2017

%Y Cf. A000312 All endofunctions

%Y Cf. A000169 Classes under translation mod n

%Y Cf. A001700 Classes under sort

%Y Cf. A056665 Classes under rotation

%Y Cf. A168658 Classes under complement to n+1

%Y Cf. A130293 Classes under translation and rotation

%Y Cf. A081721 Classes under rotation and reversal

%Y Cf. A275549 Classes under reversal

%Y Cf. A275550 Classes under reversal and complement

%Y Cf. A275551 Classes under translation and reversal

%Y Cf. A275552 Classes under translation and complement

%Y Cf. A275554 Classes under translation, rotation and complement

%Y Cf. A275555 Classes under translation, rotation and reversal

%Y Cf. A275556 Classes under translation, rotation, complement and reversal

%Y Cf. A275557 Classes under rotation and complement

%Y Cf. A275558 Classes under rotation, complement and reversal

%K nonn

%O 0,3

%A _Olivier GĂ©rard_, Aug 05 2016

%E Terms a(8) and beyond from _Andrew Howroyd_, Sep 30 2017