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Triangle read by rows: prime numbers p(n) along left edge (n, 1) and p(n - 1) along right edge (n, n), with (n, k) = rad((n - 1, k - 1) + (n - 1, k)), multiplied by two if four divides (n - 1, k - 1) + (n - 1, k), for 1 < k < n when n > 2.
1

%I #2 Mar 31 2012 10:28:53

%S 2,3,2,5,5,3,7,10,4,5,11,17,14,3,7,13,28,31,17,10,11,17,41,59,12,3,21,

%T 13,19,58,20,71,15,12,34,17,23,77,78,91,86,3,46,51,19,29,20,155,13,

%U 177,89,7,97,70,23,31,7,35,84,190,266,12,52,167,93,29

%N Triangle read by rows: prime numbers p(n) along left edge (n, 1) and p(n - 1) along right edge (n, n), with (n, k) = rad((n - 1, k - 1) + (n - 1, k)), multiplied by two if four divides (n - 1, k - 1) + (n - 1, k), for 1 < k < n when n > 2.

%C Among the initial terms, 12 occurs most frequently. 3 and 17 are also common.

%e (7, 2) = 41

%e (7, 3) = 59

%e 41 + 59 = 100

%e rad(100) = A007947(100) = 10

%e Four divides 100, so (8, 3) = 20.

%Y Cf. A000040, A007947, A144100

%K easy,nonn,tabl

%O 1,1

%A _Reikku Kulon_, Sep 17 2008