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 A175893 a(n) = m such that 2*prime(m)+prime(m+1) is prime. 0
 1, 2, 3, 6, 7, 8, 10, 17, 22, 27, 29, 30, 35, 45, 48, 49, 50, 52, 53, 57, 61, 68, 70, 80, 81, 85, 94, 104, 106, 117, 120, 125, 126, 127, 131, 132, 136, 137, 138, 143, 146, 156, 157, 166, 177, 191, 198, 206, 220, 223, 224, 225, 233, 236, 244, 248, 254, 259, 261, 262 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA a(n) = pi(A173971(n))=A000720(A173971(n)). PROG (PARI) {a=2; for(n=1, 1000, b=nextprime(a+1); isprime(2*a+b)&print1(n, ", "); a=b) CROSSREFS Cf. A000040 The prime numbers. A173971 Primes p such that 2*p+NextPrime are prime numbers. A000720 pi(n), the number of primes <= n. Sequence in context: A072685 A119960 A015841 * A031470 A047223 A004435 Adjacent sequences:  A175890 A175891 A175892 * A175894 A175895 A175896 KEYWORD easy,nonn AUTHOR Zak Seidov, Oct 10 2010 STATUS approved

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Last modified May 18 09:19 EDT 2013. Contains 225419 sequences.