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%I #11 Nov 15 2014 16:48:47
%S 1,8,34,90,208,376,628,816,1218,1768,2200,2922,3648,4342,5028,5988,
%T 7728,8478,10116,11572,12628,14298,16018,17710,21630,23128,24616,
%U 26856,28666,30622,35686,38382,42606,44062,50212,52698,56362,60798,63960,68680,73210,76200,82702,85498,90028,92136,101068,109492,114180,119308,126052,133122
%N Main diagonal of square arrays A114881 and A249741.
%C One less than the main diagonal of square arrays A083140 and A083221 formed from the sieve of Eratosthenes.
%F a(1) = 1, a(n) = (A000040(n) * A000040(2*(n-1))) - 1. [Where A000040(n) gives the n-th prime, p_n].
%F a(n) = A083140(n,n) - 1 = A083221(n,n) - 1.
%F a(n) = A083141(n+1)-1. [With the current starting offset 2 of A083141].
%o (Scheme) (define (A249743 n) (if (= 1 n) n (- (* (A000040 n) (A000040 (+ n n -2))) 1)))
%Y One less than A083141.
%Y Cf. A000040, A083140, A083221, A114881, A249741.
%K nonn
%O 1,2
%A _Antti Karttunen_, Nov 15 2014
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