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 A158846 Primes which are removed with the algorithm of A156284, starting the selection with the interval (2^4, 2^5). 4
 19, 29, 41, 47, 53, 59, 61, 97, 149, 167, 173, 233, 239, 251, 271, 283, 313, 331, 349, 373, 409, 433, 439, 499, 509, 521, 557, 563, 593, 641, 677, 743, 761, 797, 827, 887, 911, 941, 953, 1013, 1019, 1021, 1039, 1051, 1129, 1171, 1237, 1279, 1291 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS We iteratively scan integer intervals (2^(m-1)..2^m), first the one with m=5, then m=6, m=7, etc., and start with the set S={3,5,7,11,...} of all odd primes. For each prime p = 2^m-k, 2^(m-1) < p < 2^m, p is removed from S if k is in S. Basically, all the upper primes of primes pairs are removed when the prime pair sums to a power of 2 which are larger than 2^4. The sequence shows all p that are removed from S at any stage m. Powers 2^m, m >= 5, are not expressible as sums of two primes which are not in the sequence. LINKS MAPLE A158846 := proc()         local mmax, prrem, m, prm, pi, p, q ;         mmax := 12 ; prrem := {} ;         for m from 5 to mmax do                 prm := {} ;                 for pi from 1 do                         k := ithprime(pi) ;                         p := 2^m-k ;                         if p <= 2^(m-1) then  break; end if;                         if isprime(p) and not k in prrem then prm := prm union {p} ;                         end if ;                 end do:                 prrem := prrem union prm ;         end do: print( sort(prrem)) ; return ; end proc: A158846() ; # R. J. Mathar, Dec 07 2010 CROSSREFS Cf. A156284, A158756, A156759. Sequence in context: A329106 A109276 A133765 * A157026 A240724 A274849 Adjacent sequences:  A158843 A158844 A158845 * A158847 A158848 A158849 KEYWORD nonn AUTHOR Vladimir Shevelev, Mar 28 2009 STATUS approved

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Last modified May 25 02:55 EDT 2022. Contains 354047 sequences. (Running on oeis4.)