A358406 The index of A358405 where n first appears, or 0 if n never appears.

1, 3, 5, 10, 16, 8, 19, 141, 14, 190, 25, 22, 416, 70, 54, 162, 32, 308, 169, 67, 93, 203, 118, 513, 196, 29, 40, 200, 861, 37, 74, 1081, 82, 216, 208, 363, 90, 46, 375, 1675, 1091, 333, 1407, 812, 166, 78, 51, 1099, 115, 193, 1243, 64, 595, 98, 58, 367, 617, 235, 325, 766, 2137, 272, 124

Offset: 0

Author

Scott R. Shannon, Nov 14 2022

Keywords

• nonn

Comments

See A358405 for further details.

Crossrefs

Cf. A358405, A358402, A358403, A181391.

Programs

Python

from itertools import count, islice
def agen():
    k, an, first, prev = 0, 0, {0: 1}, {0: 1}
    for n in count(2):
        while k in first: yield first[k]; k += 1
        an1 = 0 if first[an] == n-1 else max(n-1-prev[an], first[an])
        if an1 not in first: first[an1] = prev[an1] = n
        prev[an] = n-1
        an = an1
print(list(islice(agen(), 63))) # Michael S. Branicky, Nov 14 2022