A035500 Shuffles at which new cards appear on top of deck in Guy's shuffling problem A035485.

0, 1, 2, 4, 5, 6, 8, 10, 11, 12, 13, 14, 16, 17, 18, 19, 20, 21, 22, 25, 26, 28, 29, 30, 32, 33, 35, 37, 38, 39, 40, 44, 46, 47, 48, 49, 51, 52, 53, 54, 55, 57, 60, 62, 64, 65, 66, 72, 73, 76, 77, 78, 83, 84, 85, 86, 87, 88, 89, 90, 91, 94, 95, 97, 98, 99, 101, 102, 103, 104

Offset

1,3

References

D. Gale, Mathematical Entertainments: "Careful Card-Shuffling and Cutting Can Create Chaos," Mathematical Intelligencer, vol. 14, no. 1, 1992, pages 54-56.

D. Gale, Tracking the Automatic Ant and Other Mathematical Explorations, A Collection of Mathematical Entertainments Columns from The Mathematical Intelligencer, Springer, 1998.

Links

Lars Blomberg, Table of n, a(n) for n = 1..10000

Prog

(Python)
from itertools import count, islice
def agen(): # generator of terms
    deck = []; tops = {1}; yield 0
    for n in count(1):
        deck += [2*n-1, 2*n]
        first, next = deck[:n], deck[n:2*n]
        deck[0:2*n:2], deck[1:2*n:2] = next, first
        if deck[0] not in tops: tops.add(deck[0]); yield n
print(list(islice(agen(), 70))) # Michael S. Branicky, Aug 11 2022

Crossrefs

Cf. A035485, A035493, A035501.

Sequence in context: A114318 A169956 A342495 * A080653 A115836 A176554

Adjacent sequences: A035497 A035498 A035499 * A035501 A035502 A035503

Keyword

nonn

Author

N. J. A. Sloane, Wouter Meeussen

Extensions

Extended (and corrected) by Jud McCranie

Status

approved