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A106727 Triangle T(n,k) = (f(n+1)*f(k+1) mod 10), where f(j) = 10 - (prime(j+3) mod 10), read by rows.

%I A106727 #23 Sep 11 2021 15:12:14
%S A106727 9,7,1,1,3,9,9,7,1,9,3,9,7,3,1,1,3,9,1,7,9,3,9,7,3,1,7,1,7,1,3,7,9,3,
%T A106727 9,1,9,7,1,9,3,1,3,7,9,7,1,3,7,9,3,9,1,7,1,1,3,9,1,7,9,7,3,1,3,9,9,7,
%U A106727 1,9,3,1,3,7,9,7,1,9,1,3,9,1,7,9,7,3,1,3,9,1,9
%N A106727 Triangle T(n,k) = (f(n+1)*f(k+1) mod 10), where f(j) = 10 - (prime(j+3) mod 10), read by rows.
%H A106727 G. C. Greubel, <a href="/A106727/b106727.txt">Rows n = 0..50 of the triangle, flattened</a>
%F A106727 T(n, k) = (f(n+1)*f(k+1) mod 10) where f(j) = 10 - (prime(j+3) mod 10).
%e A106727 Triangle begins:
%e A106727   9;
%e A106727   7, 1;
%e A106727   1, 3, 9;
%e A106727   9, 7, 1, 9;
%e A106727   3, 9, 7, 3, 1;
%e A106727   1, 3, 9, 1, 7, 9;
%e A106727   3, 9, 7, 3, 1, 7, 1;
%t A106727 f[n_]:= 10 - Mod[Prime[n+3], 10];
%t A106727 Table[Mod[f[n+1]*f[k+1], 10], {n,0,15}, {k,0,n}]//Flatten
%o A106727 (Sage)
%o A106727 def f(n): return 10 - (nth_prime(n+3)%10)
%o A106727 def A106727(n,k): return (f(n+1)*f(k+1))%10
%o A106727 flatten([[A106727(n,k) for k in (0..n)] for n in (0..15)]) # _G. C. Greubel_, Sep 10 2021
%Y A106727 Cf. A007652, A072003.
%K A106727 nonn,easy,base,less,tabl
%O A106727 0,1
%A A106727 _Roger L. Bagula_, May 14 2005