Smallest positive number of "triangular" shuffles of n(n+1)/2 cards needed to restore them to their original order.

A048782

Smallest positive number of "triangular" shuffles of n(n+1)/2 cards needed to restore them to their original order.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =6a(4) =10a(5) =84a(6) =70a(7) =24a(8) =36a(9) =330a(10) =210a(11) =288a(12) =1428a(13) =252a(14) =10080a(15) =13680a(16) =1260a(17) =19320a(18) =2160a(19) =22440a(20) =1692152a(21) =50400a(22) =140760a(23) =3071880a(24) =284088a(25) =608753236a(26) =617760a(27) =15600a(28) =35287560a(29) =214138080

External references