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A153404
Middle of 3 consecutive prime numbers such that p1*p2*p3 + d1 + d2 - 1 = average of twin prime pairs, d1 (delta) = p2 - p1, d2 (delta) = p3 - p2.
5
5, 571, 1753, 5113, 6949, 9283, 11047, 14401, 24859, 25171, 26203, 31159, 34471, 41719, 42397, 45289, 61099, 62533, 80611, 82141, 90001, 91969, 92347, 93811, 98377, 98887, 103591, 105907, 111373, 117133, 120997, 122827, 128413, 135607
OFFSET
1,1
LINKS
EXAMPLE
3*5*7 + 2 + 2 - 1 = 108 and 108 +- 1 are primes.
MATHEMATICA
lst={}; Do[p1=Prime[n]; p2=Prime[n+1]; p3=Prime[n+2]; d1=p2-p1; d2=p3-p2; a=p1*p2*p3+d1+d2-1; If[PrimeQ[a-1]&&PrimeQ[a+1], AppendTo[lst, p2]], {n, 8!}]; lst
KEYWORD
nonn
AUTHOR
STATUS
approved