A374221 Indices of 1's in A374200, where A374200 is the minimum value of A347381 that it obtains among unitary divisors of n larger than 1.

3, 4, 5, 12, 15, 20, 21, 24, 33, 35, 36, 39, 40, 44, 45, 48, 51, 52, 55, 57, 60, 65, 68, 69, 75, 76, 80, 85, 87, 92, 93, 95, 96, 100, 105, 108, 111, 115, 116, 120, 123, 124, 129, 132, 135, 141, 145, 147, 148, 155, 156, 159, 160, 164, 165, 168, 172, 177, 180, 183, 185, 188, 189, 192, 195, 196, 201, 204, 205, 212, 213

Offset: 1

Author

Antti Karttunen, Jul 09 2024

Keywords

• nonn

Comments

It seems that for all odd terms x in this sequence, A374204(x) = 1, and they form a subsequence of all terms k for which A374204(k) = 1, that might be sequence A086748.

Links

• Antti Karttunen, Table of n, a(n) for n = 1..20001

Crossrefs

Cf. A000203, A005940, A347381, A374200, A374204, A374220 (characteristic function).

Cf. also A086748 and A347391 (very likely a subsequence).

Programs

PARI

isA374221 = A374220;