A343998 a(n) = A343997(n)/2.

1, 2, 1, 4, 2, 2, 3, 8, 4, 2, 5, 4, 6, 4, 3, 16, 8, 4, 9, 8, 3, 6, 11, 8, 12, 6, 13, 4, 14, 8, 15, 32, 6, 8, 7, 4, 18, 10, 6, 8, 20, 10, 21, 16, 5, 12, 23, 16, 24, 12, 9, 20, 26, 14, 5, 24, 9, 14, 29, 8, 30, 16, 14, 64, 13, 6, 33, 8, 12, 10, 35, 32, 36, 18, 12, 28, 11, 6, 39, 32, 40, 20, 41, 24, 17, 22

Offset

1,2

Links

Table of n, a(n) for n=1..86.

Prog

(Python)
from sympy.ntheory.modular import crt
from sympy import factorint
from itertools import product
def A343998(n):
    fs = factorint(2*n)
    plist = [p**fs[p] for p in fs]
    return (1+min(k for k in (crt(plist, d)[0] for d in product([0, -1], repeat=len(plist))) if k > 0))//2 # Chai Wah Wu, Jun 01 2021

Crossrefs

Cf. A343997.

Sequence in context: A136693 A348045 A086685 * A374015 A300586 A094571

Adjacent sequences: A343995 A343996 A343997 * A343999 A344000 A344001

Keyword

nonn

Author

N. J. A. Sloane, Jun 01 2021

Status

approved