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 A225584 Primes in the chain of repeated application of x->2*x+3, starting at x=23. 3
 23, 101, 829, 6653, 13309, 6815741, 436207613, 13958643709, 27917287421, 468374361246531581, 3746994889972252669, 959230691832896684029, 16093220510709943573688614909 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Primes in A156202. LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..31 MATHEMATICA Select[NestList[2 # + 3 &, 23, 30], PrimeQ] (* or *) Select[Table[13 2^(n+1) - 3, {n, 0, 150}], PrimeQ] PROG (MAGMA) x:=23; 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 13*2^n-3] CROSSREFS Primes of the form k*2^m-3: A050415 (k=1), A173769 (k=5), A225582 (k=7), A225583 (k=11), this sequence (k=13); A172156 (k=100), A163589 (k=715). Numbers of the form 13*2^m-3: A156202. Sequence in context: A142132 A140375 A142173 * A214092 A139976 A241746 Adjacent sequences:  A225581 A225582 A225583 * A225585 A225586 A225587 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, May 14 2013 STATUS approved

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Last modified April 18 10:08 EDT 2021. Contains 343087 sequences. (Running on oeis4.)