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A225587
a(n) is the smallest prime of the form prime(n)*q + prime(n) + q, where q is an odd prime.
1
11, 23, 23, 31, 47, 83, 71, 79, 191, 179, 127, 151, 167, 263, 191, 431, 239, 743, 271, 431, 443, 479, 503, 359, 587, 1223, 1871, 431, 439, 683, 6143, 1583, 827, 839, 599, 607, 631, 983, 2351, 2087, 719, 727, 1151, 1163, 1187, 2399, 2543, 2687, 911, 919
OFFSET
1,1
COMMENTS
The odd primes q minimizing prime(n)*q + prime(n) + q are listed in A225581.
LINKS
FORMULA
a(n) = (1+prime(n))*A225581(n) + prime(n).
EXAMPLE
a(1) = 11 because prime(1) = 2 and the minimal prime of the form 2*q+2+q with q an odd prime is 11 = 2*3+2+3.
MATHEMATICA
a[n_] := Block[{q = 3, v, p = Prime@n}, While[! PrimeQ[v = p q + p + q], q = NextPrime@q]; v]; Array[a, 50] (* Giovanni Resta, May 11 2013 *)
CROSSREFS
Sequence in context: A352868 A119815 A046624 * A143584 A134773 A226662
KEYWORD
nonn,easy
AUTHOR
John-Å. W. Olsen, May 11 2013
EXTENSIONS
a(26)-a(50) from Giovanni Resta, May 11 2013
STATUS
approved