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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The odd primes q minimizing prime(n)*q + prime(n) + q are listed in A225581.

LINKS

John-Å. W. Olsen, Table of a(n), for n = 1..1000

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

Cf. A225581, A000040.

Sequence in context: A032663 A119815 A046624 * A143584 A134773 A226662

Adjacent sequences:  A225584 A225585 A225586 * A225588 A225589 A225590

KEYWORD

nonn,easy

AUTHOR

John-Å. W. Olsen, May 11 2013

EXTENSIONS

a(26)-a(50) from Giovanni Resta, May 11 2013

STATUS

approved

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Last modified September 26 21:46 EDT 2020. Contains 337377 sequences. (Running on oeis4.)