%I #16 Nov 07 2015 08:33:46
%S 0,1,2,5,6,7,14,16,21,23,24,25,26,29,54,55,60,67,80,82,86,94,105,107,
%T 111,119,120,121,122,125,126,127,134,136,141,143,264,265,266,269,288,
%U 289,314,316,339,341,390,391,396,403,414,415,444,450,469
%N Positions of involutions (permutations whose square is the identity) in reverse colexicographic order (A055089/A195663).
%H Robert Israel, <a href="/A014489/b014489.txt">Table of n, a(n) for n = 0..3996</a>
%p N:= 100: # to get a(0) to a(N)
%p M:= 0: A[0]:= 0: count:= 0:
%p for m from 2 while count < N do
%p P:= remove(t -> t[1]=1, combinat:-permute(m));
%p P:= map(t -> ListTools:-Reverse(subs([seq(i=m+1-i,i=1..m)],t)),P);
%p R:= select(t -> max(map(nops,convert(P[t],disjcyc))) = 2, [$1..nops(P)]);
%p for r in R do
%p count:= count+1;
%p A[count]:= r+M;
%p if count = N then break fi;
%p od:
%p M:= M + nops(P);
%p od:
%p seq(A[i],i=0..count); # _Robert Israel_, Oct 28 2015
%Y Positions of zeros in A261099.
%Y From a(1)=1 onward also positions of 2's in A055092.
%Y Subsequences: A060112, A064640.
%Y Cf. A055089, A195663.
%Y Cf. also A261220.
%K nonn
%O 0,3
%A _Wouter Meeussen_
%E Name changed by _Antti Karttunen_, Aug 30 2015