A109580 Primes in A109579.
3, 3, 7, 7, 11, 11, 11, 11, 13, 13, 17, 17, 17, 17, 23, 23, 29, 29, 29, 29, 61, 61, 71, 71, 71, 71, 83, 83, 83, 83, 83, 83, 107, 107, 107, 107, 137, 137, 137, 137, 137, 137, 137, 137, 149, 149, 193, 193, 227, 227, 227, 227, 227, 227, 241, 241, 241, 241, 281, 281, 307
Offset: 1
Keywords
Programs
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Maple
with(numtheory): a:=proc(n) if isprime(sum((pi(k+1)-pi(k))*(ithprime(k+1)-ithprime(k)),k=1..n))=true then sum((pi(k+1)-pi(k))*(ithprime(k+1)-ithprime(k)),k=1..n) else fi end: seq(a(n),n=1..230);
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Mathematica
an = Table[(PrimePi[n + 1] - PrimePi[n])*(Prime[n + 1] - Prime[n]), {n, 1, 400}] a[0] = 0; a[n_] := a[n] = a[n - 1] + an[[n]] aa = Flatten[Table[If[PrimeQ[a[n]] == True, a[n], {}], {n, 0, Length[an]}]]