A143538 - OEIS

A143538

Triangle read by rows, T(n,k) = 1 if k is prime, 0 otherwise; 1 <= k <= n.

0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1

(list; table; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Triangle read by rows, T(n,k) = 1 if k is prime, 0 otherwise; 1 <= k <= n. A000012 * (A010051 * 0^(n-k)). A010051 * 0^(n-k) = an infinite lower triangular matrix with A010051 (the characteristic function of the primes) as the main diagonal and the rest zeros. The multiplier A000012 takes partial sums of column terms.

LINKS

G. C. Greubel, Table of n, a(n) for the first 100 rows, flattened

FORMULA

a(n) = A010051(A002260(n)). - Wesley Ivan Hurt, Sep 20 2021

EXAMPLE

First few rows of the triangle =

0, 1;

0, 1, 1;

0, 1, 1, 0;

0, 1, 1, 0, 1;

0, 1, 1, 0, 1, 0;

0, 1, 1, 0, 1, 0, 1;