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A146764
Primes not in A075255.
1
13, 61, 73, 109, 151, 181, 229, 241, 257, 293, 307, 313, 349, 353, 373, 397, 409, 487, 509, 557, 571, 577, 601, 613, 643, 653, 661, 709, 727, 733, 739, 751, 761, 773, 811, 823, 937, 941, 977
OFFSET
1,1
COMMENTS
It has been asked whether A146071 contains all primes. The answer is no: since A075255(n) > n/2-2 for nonprime n, any prime p that did not appear until the rank 2(p+2) is not in A075255. This is a sufficient condition for not being in A146071, but unless proved otherwise, there may be primes in A075255, i.e., not listed here, which nevertheless do not appear in A146071.
PROG
(PARI) A146764( END=999 )=local( n=1, t=0, k); forprime( p=1, END, while( n<2*(p+2), isprime( k=A075255(n++)) || next; t=bitor(1<<primepi(k), t)); bittest(t, primepi(p)) || print1(p", "))
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
M. F. Hasler, Nov 04 2008
STATUS
approved