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Numbers whose proper divisors can be arranged in such a way that all sums of adjacent pairs are primes.
1

%I #6 Oct 02 2013 15:12:40

%S 4,6,8,10,12,22,30,34,58,82,118,142,202,214,274,298,358,382,394,454,

%T 478,538,562,622,694,838,862,922,1038,1042,1138,1198,1234,1282,1318,

%U 1618,1642,1654,1714,1762,2038,2062,2098,2122,2182,2302,2458,2554,2578,2602

%N Numbers whose proper divisors can be arranged in such a way that all sums of adjacent pairs are primes.

%C A096158(a(n)) > 0; subsequence of A096157.

%e Proper divisors of 30 are {1,2,3,5,6,10,15}: [3,10,1,6,5,2,15] -> (3+10,10+1,1+6,6+5,5+2,2+15) = (13,11,7,11,7,17): therefore 12 is a term.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Jun 18 2004

%E More terms from _Ryan Propper_, Jul 22 2005