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%I #16 Dec 16 2024 14:27:51
%S 1,2,3,6,7,14,21,42,1,2,3,4,5,6,10,12,15,20,30,60,1,2,4,5,8,10,16,20,
%T 40,80,1,2,4,5,10,20,25,50,100,1,2,3,4,5,6,8,10,12,15,20,24,30,40,60,
%U 120,1,2,73,146,1,2,3,4,6,7,8,12,14,21,24,28,42,56,84,168,1,2,3,4,6,8,12,16,24,32,48,64,96,192,1,2,107,214
%N Irregular triangle read by rows where row n lists the divisors of prime(4*n+8) + 2*n + 3.
%e Triangle begins:
%e k=1 2 3 4 5 6 7 8
%e n=1: 1, 2, 3, 6, 7, 14, 21, 42 (A018258)
%e n=2: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60 (A018266)
%e ...
%t Flatten[Table[Flatten[Divisors[2*n+3+Prime[4*n+8]]],{n,1,30}]]
%o (Magma) [Divisors(NthPrime(4*n+8)+(2*n+3)): n in [1..40]];
%Y Cf. A018258, A018266, A018275, A018283, A018293, A018314, A018328, A018354, A018362, A018377, A018386, A018402, A018418, A018444, A018461, A018474, A018489, A018500, A018514, A018535, A018554, A018569, A018583, A018623, A018643, A018658, A018674, A018727, A018742, A018761.
%K nonn,less,tabf
%O 1,2
%A _Vincenzo Librandi_, Dec 01 2024