A062241 Smallest integer >= 2 that is not the sum of 2 positive integers whose prime factors are all <= p(n), the n-th prime.
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
Offset: 0
Examples
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.
References
- Computed by David W. Wilson, Jun 29 2001.
Crossrefs
So far it agrees with A045535. Is this a coincidence or a theorem?
Extensions
More terms from Jud McCranie, Nov 01 2001
a(23)-a(29) from Donovan Johnson, Aug 31 2010
Comments