A118683 Triangle, T(n,k) = A039701(n) + A039701(k) - A039701(n)*A039701(k), read by rows.

0, 2, 0, 0, 2, 0, 1, 1, 1, 1, 0, 2, 0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 2, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 0, 1, 0, 1, 0, 1, 0, 0, 2, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

Offset

1,2

Links

G. C. Greubel, Rows n = 1..50 of the triangle, flattened

Example

Triangle begins as:
  0;
  2, 0;
  0, 2, 0;
  1, 1, 1, 1;
  0, 2, 0, 1, 0;
  1, 1, 1, 1, 1, 1;
  0, 2, 0, 1, 0, 1, 0;
  1, 1, 1, 1, 1, 1, 1, 1;
  0, 2, 0, 1, 0, 1, 0, 1, 0;
  0, 2, 0, 1, 0, 1, 0, 1, 0, 0;

Mathematica

A039701[n_]:= Mod[Prime[n], 3];
T[n_, k_]:= A039701[n] +A039701[k] -A039701[n]*A039701[k];
Table[T[n, k], {n, 12}, {k, n}]//Flatten

Prog

(Magma)
A039701:= func< n | NthPrime(n) mod 3 >;
A118683:= func< n, k | A039701(n)+A039701(k)-A039701(n)*A039701(k) >;
[A118683(n, k): k in [1..n], n in [1..12]]; // G. C. Greubel, Apr 01 2024
(SageMath)
def A039701(n): return nth_prime(n)%3
def A118683(n, k): return A039701(n)+A039701(k)-A039701(n)*A039701(n)
flatten([[A039701(n, k) for k in range(1, n+1)] for n in range(1, 13)]) # G. C. Greubel, Apr 01 2024

Crossrefs

Cf. A039701, A099618 (right diagonal).

Sequence in context: A219491 A305714 A324730 * A175800 A344981 A161116

Adjacent sequences: A118680 A118681 A118682 * A118684 A118685 A118686

Keyword

nonn,tabl,less,easy

Author

Roger L. Bagula, May 19 2006

Extensions

Offset corrected, definition clarified, sequence extended by Assoc. Eds. of the OEIS, Jun 15 2010

Status

approved