A362966 Numbers k such that A007908(k) == 1 (mod k).

1, 121487, 293957, 13449179, 549999887

Offset

1,2

Comments

a(6) > 10^11. - Jason Yuen, Oct 12 2024

Links

Table of n, a(n) for n=1..5.

Prog

(Python) # See A029455 for concat_mod
def isok(k): return concat_mod(10, k, k)==1%k # Jason Yuen, Oct 12 2024

Crossrefs

Cf. A007908, A029455, A029479, A110740.

Sequence in context: A228510 A237247 A068136 * A236826 A135495 A067384

Adjacent sequences: A362963 A362964 A362965 * A362967 A362968 A362969

Keyword

nonn,base,hard,more

Author

Max Alekseyev, Jun 06 2023

Status

approved