

A123929


Similiprimes 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
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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



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



KEYWORD

easy,nonn


AUTHOR



STATUS

approved



