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A163488
Primes p such that 5*p is a sum of 3 consecutive primes.
0
2, 3, 47, 79, 113, 197, 227, 257, 263, 317, 347, 383, 431, 443, 491, 499, 541, 557, 617, 757, 811, 887, 929, 977, 1021, 1087, 1093, 1129, 1231, 1237, 1433, 1511, 2111, 2129, 2213, 2347, 2543, 2551, 2609, 2657, 2671, 2803, 2837, 2999, 3011, 3049, 3119, 3187
OFFSET
1,1
COMMENTS
Primes of the form A034961(k)/5, associated with k=1, 2, 21, 31, 42, 66,... - R. J. Mathar, Aug 02 2009
EXAMPLE
p=2 is in the sequence because 2*5=10=2+3+5.
p=3 is in the sequence because 3*5=15=3+5+7.
MATHEMATICA
lst={}; Do[If[PrimeQ[p=(Prime[n]+Prime[n+1]+Prime[n+2])/5], AppendTo[lst, p]], {n, 7!}]; lst
cp3Q[n_]:=Module[{mid=Floor[PrimePi[(5n)/3]], tst}, tst=Total/@ Partition[ Prime[ Range[mid-10, mid+10]], 3, 1]; MemberQ[tst, 5n]]; Select[ Prime[ Range[ 500]], cp3Q]//Quiet (* Harvey P. Dale, Jan 02 2018 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Entries checked by R. J. Mathar, Aug 02 2009
STATUS
approved