Number of rounds of shuffling required to restore a deck of n cards to its original order: shuffling is done by keeping first card, putting second at end of deck, keeping next, putting next at end and so on.

A051732

Number of rounds of shuffling required to restore a deck of n cards to its original order: shuffling is done by keeping first card, putting second at end of deck, keeping next, putting next at end and so on.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =2a(4) =3a(5) =5a(6) =6a(7) =6a(8) =4a(9) =9a(10) =4a(11) =28a(12) =10a(13) =9a(14) =14a(15) =12a(16) =5a(17) =70a(18) =18a(19) =24a(20) =10a(21) =7a(22) =210a(23) =126a(24) =110a(25) =60a(26) =26a(27) =120a(28) =9a(29) =29

External references