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%I A154728
%S A154728 1729,7657,21793,49321,97051,175741,298351,386389,559399,789289,1089019,
%T A154728 1425829,1924177,2665603,3295273,3864241,4631971,5694079,6951667,
%U A154728 8103877,9363547,10775137,12307147,14956219,18091147,21243961,24066037
%N A154728 Products of three consecutive primes of the form 6n+1 (see A002476).
%C A154728 Note that a(1)=1729 is the Hardy-Ramanujan number (See taxicab numbers 
               in A001235, A011541).
%e A154728 13, 19, 31 are three consecutive primes of the form 6n+1 and 13*19*31=7657. 
               [From Emeric Deutsch (deutsch(AT)duke.poly.edu), Jan 21 2009]
%p A154728 a := proc (n) if `mod`(ithprime(n), 6) = 1 then ithprime(n) else end 
               if end proc: A := [seq(a(n), n = 1 .. 100)]: seq(A[j]*A[j+1]*A[j+2], 
               j = 1 .. 30); [From Emeric Deutsch (deutsch(AT)duke.poly.edu), Jan 
               21 2009]
%Y A154728 Cf. A001235, A002476, A011541, A154716, A154717, A154729.
%Y A154728 Sequence in context: A062924 A130859 A154716 this_sequence A033502 A050794 
               A138130
%Y A154728 Adjacent sequences: A154725 A154726 A154727 this_sequence A154729 A154730 
               A154731
%K A154728 easy,nonn
%O A154728 1,1
%A A154728 Omar E. Pol (info(AT)polprimos.com), Jan 18 2009, Jan 21 2009
%E A154728 Extended by Emeric Deutsch (deutsch(AT)duke.poly.edu), Jan 21 2009

    
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Last modified December 11 12:57 EST 2009. Contains 170656 sequences.


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