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A079950 Triangle of n-th prime modulo twice primes less n-th prime.

%I A079950 #10 Sep 28 2017 05:41:31
%S A079950 2,3,3,1,5,5,3,1,7,7,3,5,1,11,11,1,1,3,13,13,13,1,5,7,3,17,17,17,3,1,
%T A079950 9,5,19,19,19,19,3,5,3,9,1,23,23,23,23,1,5,9,1,7,3,29,29,29,29,3,1,1,
%U A079950 3,9,5,31,31,31,31,31,1,1,7,9,15,11,3,37,37,37,37,37,1,5,1,13,19,15,7,3,41
%N A079950 Triangle of n-th prime modulo twice primes less n-th prime.
%C A079950 The right border of the triangle are the primes: T(n,n)=A000040(n); T(n,1)=A039702(n), T(n,2)=A039704(n) for n>1, T(n,3)=A007652(n) for n>2, T(n,4)=A039712(n) for n>3;
%F A079950 T(n, k) = prime(n) mod 2*prime(k), 1<=k<=n.
%e A079950 Triangle begins:
%e A079950   2;
%e A079950   3, 3;
%e A079950   1, 5, 5;
%e A079950   3, 1, 7,  7;
%e A079950   3, 5, 1, 11, 11;
%e A079950   1, 1, 3, 13, 13, 13;
%e A079950   1, 5, 7,  3, 17, 17, 17;
%e A079950   ...
%p A079950 A079950 := proc(n,k)
%p A079950     modp(ithprime(n),2*ithprime(k)) ;
%p A079950 end proc:
%p A079950 seq(seq(A079950(n,k),k=1..n),n=1..12) ; # _R. J. Mathar_, Sep 28 2017
%o A079950 (PARI) T(n,k) = prime(n) % (2*prime(k));
%o A079950 tabl(nn) = for (n=1, nn, for (k=1, n, print1(T(n,k), ", ")); print); \\ _Michel Marcus_, Sep 21 2017
%Y A079950 Cf. A001747, A079951, A079952, A079953.
%K A079950 nonn,tabl
%O A079950 1,1
%A A079950 _Reinhard Zumkeller_, Jan 19 2003