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Search: id:A086827
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%I A086827
%S A086827 3,11,59,71,191,1151,14591,15359,138239,675839,737279,786431,22118399,
%T A086827 36175871,63700991,138412031,169869311,1321205759,4076863487,
%U A086827 10871635967,24159191039,370440929279,1793819934719,2348273369087
%N A086827 Smaller member of a twin prime pair such that the sum sets a record for 
               number of prime divisors (counted with multiplicity).
%e A086827 191:193 are twin primes and 384 has 8 prime divisors; 1151:1153 are twin 
               primes and 2304 has 10 prime divisors.
%o A086827 (PARI) g(n) = isprime(n/2 - 1) && isprime(n/2 + 1); m = 0; forprime(n 
               = 3, 10000, if (isprime(n + 2), c = bigomega(2*n + 2); if (c > m, 
               m = c; print(n)))); while (m < 50, found = 0; for (i = m - 6, m, 
               for (j = max(1, m - 1 - i), m + 4 - i, for (k = 2, 5, for (l = k, 
               15, n = 2^i*3^j*prime(k)*prime(l); if (g(n), if (!found || found 
               > n, found = n)))))); t = log(found/2^m/3)/log(1.5); t = round(t); 
               a = found/2^(m - t)/3; x = 0; i = 2^t; while (!x, if (bigomega(i) 
               >= t, n = 2^(m - t)*3*i; if (g(n), x = n)); i++); m = bigomega(x); 
               print(x/2 - 1)); (Wasserman)
%Y A086827 Sequence in context: A141776 A071698 A089188 this_sequence A164291 A137690 
               A107007
%Y A086827 Adjacent sequences: A086824 A086825 A086826 this_sequence A086828 A086829 
               A086830
%K A086827 nonn
%O A086827 0,1
%A A086827 Jason Earls (zevi_35711(AT)yahoo.com), Aug 07 2003
%E A086827 More terms from David Wasserman (wasserma(AT)spawar.navy.mil), Mar 30 
               2005

    
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Last modified December 10 12:37 EST 2009. Contains 170569 sequences.


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