A059953 Ordering of a deck of 52 cards after an out-shuffle.

1, 27, 2, 28, 3, 29, 4, 30, 5, 31, 6, 32, 7, 33, 8, 34, 9, 35, 10, 36, 11, 37, 12, 38, 13, 39, 14, 40, 15, 41, 16, 42, 17, 43, 18, 44, 19, 45, 20, 46, 21, 47, 22, 48, 23, 49, 24, 50, 25, 51, 26, 52

Offset

1,2

Links

Table of n, a(n) for n=1..52.

Eric Weisstein's World of Mathematics, Riffle Shuffle.

Mathematica

Riffle[Range[26], Range[27, 52]] (* Harvey P. Dale, Aug 17 2017 *)

Prog

(Python)
def out_shuffle(deck):
  shuffle = [i for i in range(len(deck))]
  shuffle[0::2] = deck[:(len(deck)+1)//2]
  shuffle[1::2] = deck[(len(deck)+1)//2:]
  return shuffle
print(out_shuffle(range(1, 53))) # Michael S. Branicky, Jan 27 2021

Crossrefs

Cf. A059952.

Sequence in context: A040725 A040726 A040727 * A190994 A036195 A040728

Adjacent sequences: A059950 A059951 A059952 * A059954 A059955 A059956

Keyword

nonn,easy,fini,full

Author

Eric W. Weisstein

Status

approved