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A356319
Numbers k such that {the least j >= k for which k and A276086(k+j) are coprime} is larger than 0, but less than k, where A276086 is the primorial base exp-function.
4
9, 20, 21, 25, 27, 33, 39, 40, 45, 50, 51, 55, 57, 69, 75, 80, 81, 85, 87, 93, 99, 100, 110, 111, 112, 115, 117, 119, 123, 126, 129, 130, 133, 135, 140, 141, 145, 147, 153, 159, 160, 161, 165, 168, 170, 171, 175, 177, 182, 183, 189, 190, 195, 196, 200, 201, 203, 205, 207, 213, 219, 225, 230, 235, 237, 243, 245, 249
OFFSET
1,1
COMMENTS
Numbers k for which 0 < A356302(k) < k, or equally, for which k < A356309(k) < 2*k.
PROG
(PARI) isA356319(n) = { my(u=A356302(n)); (u && (u<n)); };
CROSSREFS
Subsequence of A356317, which is a subsequence of A324584.
Sequence in context: A378229 A236205 A356317 * A050682 A094196 A253089
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 04 2022
STATUS
approved