Search: id:A007921 Results 1-1 of 1 results found. %I A007921 %S A007921 7,13,19,23,25,31,33,37,43,47,49,53,55,61,63,67,73,75,79,83,85, %T A007921 89,91,93,97,103,109,113,115,117,119,121,123,127,131,133,139,141, %U A007921 143,145,151,153,157,159,163,167,169,173,175,181,183,185,187,193 %N A007921 Numbers that are not the difference of two primes. %D A007921 F. Smarandache, Properties of Numbers, 1972. (See Smarandache odd sieve.) %D A007921 F. Smarandache, "Only Problems, not Solutions!", Xiquan Publ., Phoenix-Chicago, 1993 %H A007921 T. D. Noe, Table of n, a(n) for n=1..10000 %H A007921 C. Dumitrescu & V. Seleacu, editors, Some Notions and Questions in Number Theory, Vol. I. %H A007921 F. Smarandache, Only Problems, Not Solutions! %H A007921 Index entries for primes, gaps between %F A007921 Odd numbers n such that n+2 is composite. %Y A007921 Cf. A048859. %Y A007921 Complement of A030173. Cf. A001223. %Y A007921 Equals A005381(2n-1) - 1. %Y A007921 Sequence in context: A074628 A031194 A121058 this_sequence A092409 A124095 A109369 %Y A007921 Adjacent sequences: A007918 A007919 A007920 this_sequence A007922 A007923 A007924 %K A007921 nonn,easy,nice %O A007921 1,1 %A A007921 R. Muller Search completed in 0.001 seconds