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A144426
Primes of the form (p(n)-2*(n-1))/7, where p(n)=n-th prime.
1
7, 13, 17, 19, 23, 29, 31, 37, 37, 41, 59, 83, 89, 97, 97, 101, 101, 107, 149, 157, 167, 167, 179, 197, 199, 211, 211, 223, 241, 257, 269, 283, 283, 307, 311, 313, 331, 373, 401, 433, 439, 439, 443, 443, 463, 503, 557, 569, 587, 599, 617, 619, 619, 641, 691
OFFSET
1,1
LINKS
EXAMPLE
If n=25, then (p(25)-2*(25-1))/7=(97-48)/7=7=a(1).
If n=39, then (p(39)-2*(39-1))/7=(167-76)/7=13=a(2).
If n=47, then (p(47)-2*(47-1))/7=(211-92)/7=17=a(3).
If n=51, then (p(51)-2*(51-1))/7=(233-100)/7=19=a(4).
If n=59, then (p(59)-2*(59-1))/7=(277-116)/7=23=a(5).
If n=68, then (p(68)-2*(68-1))/7=(337-134)/7=29=a(6), etc.
MATHEMATICA
Select[(#[[2]]-2#[[1]])/7&/@Table[{n-1, Prime[n]}, {n, 1000}], PrimeQ] (* Harvey P. Dale, Jan 17 2019 *)
CROSSREFS
Cf. A000040.
Sequence in context: A205686 A072459 A158813 * A233518 A118942 A067656
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected (101, 167 and 211 duplicated, 107 inserted) and extended by R. J. Mathar, Apr 13 2010
STATUS
approved