This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A289108 #41 Aug 04 2024 20:19:59 %S A289108 1,2,5,3,7,11,5,11,17,23,7,15,23,31,39,11,23,35,47,59,71,13,27,41,55, %T A289108 69,83,97,17,35,53,71,89,107,125,143,19,39,59,79,99,119,139,159,179, %U A289108 23,47,71,95,119,143,167,191,215,239,29,59,89,119,149,179,209,239,269,299,329 %N A289108 Triangle read by rows: T(n,k) = (k + 1)*prime(n) + k for n > 0, 0 <= k <= n, and with T(0,0) = 1. %H A289108 G. C. Greubel, <a href="/A289108/b289108.txt">Rows n = 0..50 of the triangle, flattened</a> %e A289108 Triangle begins: %e A289108 1; %e A289108 2, 5; %e A289108 3, 7, 11; %e A289108 5, 11, 17, 23; %e A289108 7, 15, 23, 31, 39; %e A289108 11, 23, 35, 47, 59, 71; %e A289108 13, 27, 41, 55, 69, 83, 97; %e A289108 17, 35, 53, 71, 89, 107, 125, 143; %e A289108 19, 39, 59, 79, 99, 119, 139, 159, 179; %e A289108 23, 47, 71, 95, 119, 143, 167, 191, 215, 239; %e A289108 ... %t A289108 Join[{1}, T[n_,k_] := (k + 1) Prime[n] + k; Table[T[n, k], {n, 10}, {k, 0, n}]//Flatten] %o A289108 (Magma) /* As triangle (here NthPrime(0)=1) */ [[(k+1)*NthPrime(n)+k: k in [0..n]]: n in [0.. 15]]; %o A289108 (SageMath) %o A289108 def A289108(n,k): return 1 if n==0 else (k+1)*nth_prime(n) +k %o A289108 flatten([[A289108(n,k) for k in range(n+1)] for n in range(13)]) # _G. C. Greubel_, Aug 04 2024 %Y A289108 Cf. A000040, A008578, A072055. %K A289108 nonn,tabl %O A289108 0,2 %A A289108 _Vincenzo Librandi_, Sep 02 2017 %E A289108 Definition corrected by _Bruno Berselli_, Sep 06 2017