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 A059960 Smaller term of a pair of twin primes such that prime factors of their average are only 2 and 3. 17
 5, 11, 17, 71, 107, 191, 431, 1151, 2591, 139967, 472391, 786431, 995327, 57395627, 63700991, 169869311, 4076863487, 10871635967, 2348273369087, 56358560858111, 79164837199871, 84537841287167, 150289495621631 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Primes p(k) such that the number of distinct prime divisors of all composite numbers between p(k) and p(k+1) is 2. - Amarnath Murthy, Sep 26 2002 LINKS Ray Chandler, Table of n, a(n) for n = 1..61 (terms < 10^1000, first 49 terms from T. D. Noe) FORMULA Primes p such that p+1 = (2^u)*(3^w) EXAMPLE a(11)+1 = 2*2*2*3*3*3*3*3*3*3*3*3*3 = 472392. MATHEMATICA nn=10^15; Sort[Reap[Do[n=2^i 3^j; If[n<=nn && PrimeQ[n-1] && PrimeQ[n+1], Sow[n-1]], {i, Log[2, nn]}, {j, Log[3, nn]}]][[2, 1]]] Select[Select[Partition[Prime[Range[38*10^5]], 2, 1], #[[2]]-#[[1]]==2&][[All, 1]], FactorInteger[#+1][[All, 1]]=={2, 3}&] (* The program generates the first 15 terms of the sequence. *) CROSSREFS Cf. A014574, A002822, A033845, A058383, A027856. Cf. A052297, A075581, A075580, A075583, A075584, A075585, A075586, A075587, A075588, A075589. Apart from initial terms, same as A078883. Sequence in context: A058019 A182482 A075582 * A265850 A185365 A282669 Adjacent sequences:  A059957 A059958 A059959 * A059961 A059962 A059963 KEYWORD nonn,changed AUTHOR Labos Elemer, Mar 02 2001 STATUS approved

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Last modified September 25 00:48 EDT 2020. Contains 337333 sequences. (Running on oeis4.)