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 A123929 Simili-primes of order 2. 10
 3, 5, 8, 13, 17, 22, 28, 31, 38, 43, 47, 53, 59, 67, 73, 77, 82, 89, 97, 101, 107, 113, 121, 127, 133, 139, 148, 151, 158, 163, 167, 179, 191, 197, 203, 209, 218, 227, 233, 241, 251, 257, 262, 269, 274, 281, 284, 293, 307, 313, 317, 322, 332, 343, 347, 353, 361 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Start examining the natural numbers from 2 on and call an "atom" the first integer which cannot be divided by another "atom"; this sieve produces the prime numbers. Here we call "atom" the second integer which cannot be divided by another "atom" - thus the sequence starts with 3 (not 2) and continues with 5 (not 4), then 8 (not 6 or 7), then 13, etc. Terms computed by Mensanator. REFERENCES J.-P. Delahaye, La suite du lézard et autres inventions, Pour la Science, No. 353, 2007. LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 150 terms from a correspondent using the pseudonym "Mensanator") Eric Angelini, Thousand Zetas Eric Angelini, Thousand Zetas [Cached copy, with permission] FORMULA Conjecture : a(n) is asymptotic to c*n*log(n) with c about 1.5. - Benoit Cloitre, Feb 11 2007 PROG (PARI) A123929(n, mode=0/*+1=print, +2=return list*/, N=2, P=List(N+1))={ while(n--, my(k=P[#P]); for(i=1, N, while(k++, for(j=1, #P, k%P[j]||next(2)); break)); bittest(mode, 0)&&print1(k", "); listput(P, k)); if(bittest(mode, 1), Vec(P), P[#P])} \\ M. F. Hasler, Dec 24 2013 (PARI) v=vectorsmall(10^3); u=List(); v[n=1]=1; while(n<#v*99/100, while(v[n++], ); while(v[n++], ); listput(u, n); forstep(k=2*n, #v, n, v[k]=1)); Vec(u) \\ Charles R Greathouse IV, Jan 02 2014 CROSSREFS Cf. A126618-A126624. Sequence in context: A331467 A337289 A097431 * A036715 A337503 A310035 Adjacent sequences: A123926 A123927 A123928 * A123930 A123931 A123932 KEYWORD easy,nonn AUTHOR Eric Angelini and Hugo van der Sanden, Nov 22 2006 STATUS approved

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