A096007 Scan Pascal's triangle (A007318) from left to right, record smallest prime factor of each entry.

2, 3, 3, 2, 2, 2, 5, 2, 2, 5, 2, 3, 2, 3, 2, 7, 3, 5, 5, 3, 7, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 2, 2, 2, 3, 2, 11, 5, 3, 2, 2, 2, 2, 3, 5, 11, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 13, 2, 2, 5, 3, 2, 2, 3, 5, 2, 2, 13, 2, 7, 2, 7, 2, 3, 2, 3, 2, 7, 2, 7, 2, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3

Offset

1,1

Links

Table of n, a(n) for n=1..104.

Example

n Pascal's Triangle
1 1
2 1 2 1
3 1 3 3 1
4 1 4 6 4 1
so 2, 2, 2 = smallest prime factors of row 4 = entries position 4, 5, 6 in the sequence.

Prog

(PARI) \Smallest prime factors of numbers in Pascal's triangle. pascal(n) = { local(x, y, z, f, z1); for(x=1, n, for(y=1, x-1, z=binomial(x, y); f=Vec(factor(z)); z1=f[1][1]; print1(z1", ") ); ) }

Crossrefs

Cf. A007318.

Sequence in context: A011154 A048466 A096838 * A269043 A309952 A059252

Adjacent sequences: A096004 A096005 A096006 * A096008 A096009 A096010

Keyword

easy,nonn

Author

Cino Hilliard, Jul 25 2004

Status

approved