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%I #6 Mar 30 2012 17:34:14
%S 31,41,61,71,131,151,211,241,251,311,331,401,421,431,491,521,571,601,
%T 661,691,701,751,761,881,941,971,1021,1031,1051,1061,1151,1201,1231,
%U 1291,1301,1321,1381,1471,1481,1511,1571,1601,1741,1831,1861,1871,1931
%N Pseudofactor sets of primes ending in 1: 9 greater than 3.
%C These pseudofactors although not unique sets as their domains seem to overlap form twelve subsets of primes based on the first digit set {1,3,7,9} when {2,5} are taken away from the prime set. I'm entering the four {1}'s sets. There exist {3}'s, {7}'s and {9}'s sets of these same four types.
%F a[n]=Primes ending in one b(m) = if Mod[a[[n]]/9, 10]>3 then a[n]
%t digits=4*200 a=Delete[Union[Table[If[Mod[Prime[n], 10]==1, Prime[n], 0], {n, 1, digits}]], 1] d2=Dimensions[a][[1]] a9g3=Delete[Union[Table[If[Mod[a[[n]]/9, 10]>3, a[[n]], 0], {n, 1, d2}]], 1]
%K nonn,uned
%O 1,1
%A _Roger L. Bagula_, Jan 06 2004