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 A062241 Smallest integer >= 2 that is not the sum of 2 positive integers whose prime factors are all <= p(n), the n-th prime. 4
 3, 7, 23, 71, 311, 479, 1559, 5711, 10559, 18191, 31391, 118271, 366791, 366791, 2155919, 2155919, 2155919, 6077111, 6077111, 98538359, 120293879, 131486759, 131486759, 508095719, 2570169839, 2570169839, 2570169839, 2570169839, 2570169839, 2570169839 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Here we are taking 1 to be the zeroth prime. a(30) > 2570169839. - Donovan Johnson, Aug 31 2010 REFERENCES Computed by David W. Wilson, Jun 29 2001. LINKS EXAMPLE a(1): 2=1+1, 3=1+2, 4=2+2, 5=1+4, 6=2+4, but 7 cannot be written as the sum of two positive integers whose prime factors are all <= 2, so a(1) = 7. a(2): 7=3+4, 8=4+4, 9=1+8, ..., 22=4+18, but 23 cannot be so written, so a(2) = 23. CROSSREFS So far it agrees with A045535. Is this a coincidence or a theorem? Sequence in context: A140456 A066768 A225914 * A000229 A133435 A079061 Adjacent sequences:  A062238 A062239 A062240 * A062242 A062243 A062244 KEYWORD nonn,nice AUTHOR Richard C. Schroeppel, Jun 27 2001 EXTENSIONS More terms from Jud McCranie, Nov 01 2001 a(23)-a(29) from Donovan Johnson, Aug 31 2010 STATUS approved

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Last modified December 5 05:51 EST 2020. Contains 338944 sequences. (Running on oeis4.)