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a(n) = prime(n+2)*prime(n+3)-prime(n)*prime(n+1).
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%I #13 Nov 02 2020 01:50:59

%S 29,62,108,144,180,216,344,462,480,618,616,504,728,1106,1108,960,1158,

%T 1096,1010,1374,1620,2076,2410,1770,1224,1260,1296,2688,4320,3596,

%U 2406,2764,3456,2996,3092,3514,3300,3746,3508,3604,4464,3450,2340,3968,7850,8632,4930,2736,3704,4242,4804,6908

%N a(n) = prime(n+2)*prime(n+3)-prime(n)*prime(n+1).

%C a(n) > (A001223(n)+2*A001223(n+1)+A001223(n+2))*prime(n).

%C In particular, a(n) > 12*prime(n).

%H Robert Israel, <a href="/A338529/b338529.txt">Table of n, a(n) for n = 1..10000</a>

%H Robert Israel, <a href="/A338529/a338529.png">Plot of a(n)/n for 1 <= n <= 30000</a>

%e The third through sixth primes are 5,7,11,13, so a(3) = 11*13-5*7 = 108.

%p seq(ithprime(n+2)*ithprime(n+3)-ithprime(n)*ithprime(n+1), n=1..1000);

%Y Cf. A338533, A338537.

%K nonn,look

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Nov 01 2020