A360600 Inverse permutation to A360599.

1, 2, 3, 5, 6, 4, 8, 9, 11, 12, 14, 15, 17, 18, 20, 21, 23, 24, 26, 7, 27, 29, 30, 32, 33, 35, 36, 38, 39, 41, 42, 44, 45, 47, 48, 50, 51, 53, 54, 56, 57, 59, 60, 62, 63, 65, 66, 68, 69, 71, 72, 74, 75, 77, 78, 10, 80, 81, 83, 84, 86, 87, 89, 90, 92, 93, 95

Offset: 1

Author

Rémy Sigrist, Feb 13 2023

Keywords

• nonn

Examples

			A360599(59) = 42, so a(42) = 59.
		

Links

• Rémy Sigrist, PARI program
• Index entries for sequences that are permutations of the natural numbers

Crossrefs

Cf. A360599.

Programs

PARI

See Links section.

Python

from itertools import islice
def agen(): # generator of terms
    an, ratios, inv, n = 1, set(), dict(), 1
    while True:
        k = 1
        q, r = divmod(max(k, an), min(k, an))
        while r != 0 or q in ratios:
            k += 1
            q, r = divmod(max(k, an), min(k, an))
        an = k
        ratios.add(q)
        inv[q] = len(ratios)
        while n in inv:
            yield inv[n]
            n += 1
print(list(islice(agen(), 67))) # Michael S. Branicky, Feb 13 2023