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A289055 Triangle read by rows: T(n,k) = (k+1)*A028815(n) for 0 <= k <= n.

%I A289055 #53 Aug 05 2024 08:40:29
%S A289055 2,3,6,4,8,12,6,12,18,24,8,16,24,32,40,12,24,36,48,60,72,14,28,42,56,
%T A289055 70,84,98,18,36,54,72,90,108,126,144,20,40,60,80,100,120,140,160,180,
%U A289055 24,48,72,96,120,144,168,192,216,240,30,60,90,120,150,180,210,240,270,300,330
%N A289055 Triangle read by rows: T(n,k) = (k+1)*A028815(n) for 0 <= k <= n.
%H A289055 G. C. Greubel, <a href="/A289055/b289055.txt">Rows n = 0..50 of the triangle, flattened</a>
%F A289055 a(n) = A289108(n) + 1.
%e A289055 Triangle begins:
%e A289055    2;
%e A289055    3,   6;
%e A289055    4,   8,  12;
%e A289055    6,  12,  18,  24;
%e A289055    8,  16,  24,  32,  40;
%e A289055   12,  24,  36,  48,  60,  72;
%e A289055   14,  28,  42,  56,  70,  84,  98;
%e A289055   18,  36,  54,  72,  90, 108, 126, 144;
%e A289055   20,  40,  60,  80, 100, 120, 140, 160, 180;
%e A289055   ...
%t A289055 Join[{2}, t[n_, k_] := (k + 1) (Prime[n] + 1); Table[t[n, k], {n, 10}, {k, 0, n}] //Flatten]
%o A289055 (Magma) /* As triangle (here NthPrime(0)=1) */ [[(k+1)*(NthPrime(n)+1): k in [0..n]]: n in [0.. 15]];
%o A289055 (SageMath)
%o A289055 def A289055(n,k): return 2 if n==0 else (k+1)*(nth_prime(n) +1)
%o A289055 flatten([[A289055(n,k) for k in range(n+1)] for n in range(13)]) # _G. C. Greubel_, Aug 05 2024
%Y A289055 Cf. A289108.
%Y A289055 Columns k: A028815 (k=0), A089241 (k=1), A247159 (k=2), A273801 (k=3).
%K A289055 nonn,tabl,less
%O A289055 0,1
%A A289055 _Vincenzo Librandi_, Sep 02 2017