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A225583
Primes in the chain of repeated application of x->2*x+3, starting at x=19.
3
19, 41, 173, 349, 701, 11261, 45053, 180221, 184549373, 738197501, 5905580029, 188978561021, 6192449487634429, 49539595901075453, 99079191802150909, 25364273101350633469, 811656739243220271101, 3486039150627630854115933814781
OFFSET
1,1
COMMENTS
Primes in A156198.
LINKS
MATHEMATICA
Select[NestList[2 # + 3 &, 19, 30], PrimeQ] (* or *) Select[Table[11 2^n - 3, {n, 0, 150}], PrimeQ]
PROG
(Magma) x:=19; a:=[n eq 1 select x else 2*Self(n-1)+3: n in [1..200]]; [a[i]: i in [1..#a] | IsPrime(a[i])]; /* or */ [a: n in [0..150] | IsPrime(a) where a is 11*2^n-3];
CROSSREFS
Primes of the form k*2^m-3: A050415 (k=1), A173769 (k=5), A225582 (k=7), this sequence (k=11), A225584 (k=13); A172156 (k=100), A163589 (k=715).
Numbers of the form 11*2^m-3: A156198.
Sequence in context: A141855 A323387 A328493 * A180932 A140603 A139580
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, May 14 2013
STATUS
approved