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A154668 Averages of twin prime pairs such that p1*p2-+AverageTwinPrime=primes. 0
4, 6, 60, 420, 2730, 8970, 11970, 21840, 28620, 29130, 44130, 48120, 55050, 56100, 61980, 74160, 84390, 87540, 111270, 111870, 143880, 176550, 191670, 207510, 227610, 229590, 233550, 251220, 258330, 281580, 324450, 343770, 356820, 390000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

3*5-4=11,3*5+4=19, 5*7-6=29,5*7+6=41,...

LINKS

Table of n, a(n) for n=1..34.

MATHEMATICA

lst={}; Do[If[PrimeQ[n-1]&&PrimeQ[n+1], If[PrimeQ[(n-1)*(n+1)-n]&&PrimeQ[(n-1)*(n+1)+n], AppendTo[lst, n]]], {n, 2*9!}]; lst

CROSSREFS

Cf. A154666, A154667

Sequence in context: A058162 A244388 A132929 * A189790 A053489 A012898

Adjacent sequences:  A154665 A154666 A154667 * A154669 A154670 A154671

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jan 13 2009

STATUS

approved

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Last modified October 17 10:50 EDT 2017. Contains 293469 sequences.