A368382 a(1) = 1; for n > 1, a(n) is the least positive integer not already in the sequence such that a(n) == a(n-1) (mod A004280(n)).

1, 3, 6, 11, 4, 13, 2, 15, 30, 47, 9, 51, 5, 55, 28, 57, 26, 59, 24, 61, 22, 63, 20, 65, 18, 67, 16, 69, 14, 71, 12, 73, 10, 75, 8, 77, 148, 221, 146, 223, 144, 225, 142, 227, 53, 231, 49, 235, 45, 239, 41, 243, 37, 247, 33, 251, 29, 255, 25, 259, 21, 263, 17, 267, 140, 269, 7, 273, 138, 275, 136, 277, 134, 279, 132, 281

Offset: 1

Author

N. J. A. Sloane, Mar 03 2024

Keywords

• nonn

Comments

Analogous to A364054, but whereas that sequence is based on the sequence of primes (2, 3, 5, 7, 11, ....), the present sequence is based on the sequence 2, 3, 5, 7, 9, 11, 13, 15, ... (2 together with the odd numbers >1, essentially A004280).

Links

• N. J. A. Sloane, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A004280.

Similar definitions: A005132, A006509, A364054.

Programs

Python

from itertools import count, islice
def A368382_gen(): # generator of terms
    a, aset, p = 1, {0,1}, 2
    while True:
        yield a
        for b in count(a%p,p):
            if b not in aset:
                aset.add(b)
                a, p = b, 3 if p == 2 else p+2
                break
A368382_list = list(islice(A368382_gen(),40)) # Chai Wah Wu, Mar 05 2024