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Multiplication table of the primes read by antidiagonals.
18

%I #11 Jul 05 2012 07:04:22

%S 4,6,6,10,9,10,14,15,15,14,22,21,25,21,22,26,33,35,35,33,26,34,39,55,

%T 49,55,39,34,38,51,65,77,77,65,51,38,46,57,85,91,121,91,85,57,46,58,

%U 69,95,119,143,143,119,95,69,58,62,87,115,133,187,169,187,133,115,87,62

%N Multiplication table of the primes read by antidiagonals.

%C Contains only semiprimes (A001358).

%C sum{n>=1, k>=1} 1/T(n,k)^s = P(s)^2, where P is the Prime Zeta Function. - _Enrique PĂ©rez Herrero_, Jun 24 2012

%F T(n,k) = A003991(prime(n),prime(k)).

%F T(n,k) = T(k,n) = A087112(n,k).

%e 4, 6, 10, 14, 22, 26, 34, 38, 46, 58,...

%e 6, 9, 15, 21, 33, 39, 51, 57, 69, 87,...

%e 10, 15, 25, 35, 55, 65, 85, 95,115,145,...

%e 14, 21, 35, 49, 77, 91,119,133,161,203,...

%e 22, 33, 55, 77,121,143,187,209,253,319,...

%e 26, 39, 65, 91,143,169,221,247,299,377,...

%e 34, 51, 85,119,187,221,289,323,391,493,...

%Y Cf. A098351, A006881.

%K nonn,tabl

%O 1,1

%A Douglas Stones (dssto1(AT)student.monash.edu.au), Sep 04 2004