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A141561
Primes of the form 7*k - prime(k) (terms can be repeated).
1
5, 11, 29, 37, 41, 47, 59, 79, 89, 97, 101, 103, 107, 113, 113, 127, 139, 137, 139, 149, 149, 151, 167, 167, 157, 163, 179, 179, 181, 181, 181, 181, 181, 179, 173, 181, 179, 191, 181, 179, 181, 179, 179, 191, 191, 193, 193, 179, 181, 179, 173, 179, 173, 179
OFFSET
1,1
COMMENTS
For n>=1, list 7*k-prime(k) if abs(7*k-prime(k)) is prime. Terms are negative for n >= 114. - Joerg Arndt, Sep 03 2020
Some terms appear many times. For example, in the first 1000 terms, 179 appears 12 times. There are only 755 distinct terms in the first 1000 terms. - Harvey P. Dale, Aug 15 2020
LINKS
EXAMPLE
7*60 - prime(60) = 420 - 281 = 139, so 139 appears in the sequence;
7*68 - prime(68) = 476 - 337 = 139, so 139 appears again.
MATHEMATICA
Select[Table[7n-Prime[n], {n, 250}], PrimeQ] (* Harvey P. Dale, Aug 15 2020 *)
CROSSREFS
Cf. A000040.
Sequence in context: A182379 A363645 A243544 * A240103 A019345 A279067
KEYWORD
sign,less,dumb
AUTHOR
EXTENSIONS
Edited, corrected and extended by Ray Chandler, Aug 19 2008
STATUS
approved