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%I #26 Apr 12 2019 13:11:06
%S -1,1,-1,7,-6,-1,11,-10,-6,-1,13,-12,-10,-6,-1,17,-16,-12,-10,-6,-1,
%T 19,-18,-16,-12,-10,-6,-1,23,-22,-18,-16,-12,-10,-6,-1,29,-28,-22,-18,
%U -16,-12,-10,-6,-1,31,-30,-28,-22,-18,-16,-12,-10,-6,-1,37,-36,-30,-28,-22,-18,-16,-12,-10,-6,-1
%N Triangle read by rows: T(n,0) = prime(n+2), T(n,1) = 1 - T(n,0), T(n,k) = T(n-1,k-1), T(1,0) = 1 T(n,n) = -1,
%H G. C. Greubel, <a href="/A152722/b152722.txt">Rows n = 0..50 of triangle, flattened</a>
%F T(n,n) = -1, T(1,0) = 1, T(n,0) = prime(n+2), T(n,1) = 1 - prime(n+2), T(n,k) = T(n-1,k-1). - _G. C. Greubel_, Apr 07 2019
%e Triangle begins as:
%e -1;
%e 1, -1;
%e 7, -6, -1;
%e 11, -10, -6, -1;
%e 13, -12, -10, -6, -1;
%e 17, -16, -12, -10, -6, -1;
%e 19, -18, -16, -12, -10, -6, -1;
%e 23, -22, -18, -16, -12, -10, -6, -1;
%e 29, -28, -22, -18, -16, -12, -10, -6, -1;
%t T[n_, n_]:= -1; T[1, 0]:= 1; T[n_, 0]:= Prime[n+2]; T[n_, 1]:= 1 - Prime[n+2]; T[n_, k_]:= T[n-1, k-1]; Table[T[n, k], {n, 0, 10}, {k, 0, n}]//Flatten (* _G. C. Greubel_, Apr 07 2019 *)
%o (PARI) {T(n,k) = if(k==n, -1, if(n==1 && k==0, 1, if(k==0, prime(n+2), if(k==1, 1-prime(n+2), T(n-1,k-1) ))))}; \\ _G. C. Greubel_, Apr 07 2019
%o (Sage)
%o @CachedFunction
%o def T(n,k):
%o if k==n: return -1
%o elif n==1 and k==0: return 1
%o elif k==0: return nth_prime(n+2)
%o elif k==1: return 1 - nth_prime(n+2)
%o else: return T(n-1,k-1)
%o [[T(n,k) for k in (0..n)] for n in (0..10)] # _G. C. Greubel_, Apr 07 2019
%Y Cf. A152568, A027293.
%K sign,tabl,less,obsc
%O 0,4
%A _Roger L. Bagula_ and _Alexander R. Povolotsky_, Dec 11 2008
%E Edited by _G. C. Greubel_, Apr 07 2019
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