A127966 a(n) = number of 4-times (but not 5-times) reformable permutation of {1,...,n}.

2, 1, 1, 4, 14, 57

Offset: 11

Author

Alberto M. Bersani (bersani(AT)dmmm.uniroma1.it), Feb 09 2007

Keywords

• nonn
• more

Comments

For n=16 we have the first example of a 5-reformed (but not 6-reformed) permutation: 1, 16, 12, 15, 6, 8, 14, 10, 9, 3, 4, 11, 13, 2, 7, 5 - Alberto M. Bersani (bersani(AT)dmmm.uniroma1.it), Feb 24 2008

References

• A. M. Bersani, ``Reformed permutations in Mousetrap and its generalizations,'' Preprint Me.Mo.Mat. n. 15/2005.
• R. K. Guy and R. J. Nowakowski, ``Mousetrap,'' in D. Miklos, V.T. Sos and T. Szonyi, eds., Combinatorics, Paul Erdős is Eighty. Bolyai Society Math. Studies, Vol. 1, pp. 193-206, 1993.

Links

• A. M. Bersani, On the game Mousetrap.
• R. K. Guy and R. J. Nowakowski, Mousetrap, Amer. Math. Monthly, 101 (1994), 1007-1010.

Crossrefs

Cf. A007709, A007710, A007711, A007712, A055459, A067950.

Extensions

One more term from Alberto M. Bersani (bersani(AT)dmmm.uniroma1.it), Feb 24 2008