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A156782 Primes : if sums of prime number and 4 consecutive prime numbers on-left-and-on-right are also primes. 5
19, 29, 43, 73, 137, 149, 157, 179, 211, 379, 383, 401, 409, 433, 467, 557, 569, 577, 599, 677, 839, 863, 883, 919, 997, 1103, 1303, 1499, 1553, 1637, 1669, 1709, 1783, 1811, 1861, 1873, 1951, 2113, 2207, 2309, 2393, 2503, 2647, 2663, 2713, 2791, 3011 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

7+11+13+17+19=67(prime);19+23+29+31+37=139(prime),... prime(n)+prime(n-1)+prime(n-2)+prime(n-3)+prime(n-4) are primes and prime(n)+prime(n+1)+prime(n+2)+prime(n+3)+prime(n+4) are also primes.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

lst={}; Do[p0=Prime[n+0]; p1=Prime[n+1]; p2=Prime[n+2]; p3=Prime[n+3]; p4=Prime[n+4]; p5=Prime[n+5]; p6=Prime[n+6]; p7=Prime[n+7]; p8=Prime[n+8]; If[PrimeQ[p0+p1+p2+p3+p4]&&PrimeQ[p4+p5+p6+p7+p8], AppendTo[lst, p4]], {n, 7!}]; lst

Transpose[Select[Partition[Prime[Range[500]], 9, 1], And@@PrimeQ[{Total[ Take[#, 5]], Total[Take[#, -5]]}]&]][[5]] (* Harvey P. Dale, Jul 11 2013 *)

CROSSREFS

Cf. A156781

Sequence in context: A100590 A046120 A063644 * A092600 A106124 A062679

Adjacent sequences:  A156779 A156780 A156781 * A156783 A156784 A156785

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Feb 15 2009

STATUS

approved

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Last modified March 5 11:27 EST 2021. Contains 341823 sequences. (Running on oeis4.)