A014766 Numbers k such that the 3k shuffle group does not accomplish a perfect shuffle.

9, 12, 24, 27, 36, 48, 60, 72, 81, 84, 96, 108, 120

Offset

1,1

References

W. Bosma et al., Solving Problems with Magma, Sect. 2.2.3.

Cannon and Playoust, An Introduction to MAGMA, Section 6.3.1.

Links

Table of n, a(n) for n=1..13.

P. Diaconis, The mathematics of perfect shuffles, Adv. Appl. Math. 4 (2) (1983) 175-196.

Steve Medvedoff and Kent Morrison, Groups of perfect shuffles, Math. Mag. 60 (1987), no. 1, 3-14.

Formula

Conjecture: k is in the sequence if k = 3^(m+1) or k = 12 * m for m >= 1. - Sean A. Irvine, Nov 19 2018

Crossrefs

Cf. A014525.

Sequence in context: A157973 A057577 A328069 * A182877 A114434 A105704

Adjacent sequences: A014763 A014764 A014765 * A014767 A014768 A014769

Keyword

nonn,more,nice

Author

N. J. A. Sloane

Status

approved