A098802 Greatest prime factors in Pascal's triangle (read by rows).

1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 2, 3, 2, 1, 1, 5, 5, 5, 5, 1, 1, 3, 5, 5, 5, 3, 1, 1, 7, 7, 7, 7, 7, 7, 1, 1, 2, 7, 7, 7, 7, 7, 2, 1, 1, 3, 3, 7, 7, 7, 7, 3, 3, 1, 1, 5, 5, 5, 7, 7, 7, 5, 5, 5, 1, 1, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 1, 1, 3, 11, 11, 11, 11, 11, 11, 11, 11, 11, 3, 1

Offset

0,5

Links

Table of n, a(n) for n=0..90.

Eric Weisstein's World of Mathematics, Pascal's Triangle

Eric Weisstein's World of Mathematics, Greatest Prime Factor

Index entries for triangles and arrays related to Pascal's triangle

Formula

T(n,k) = A006530(A007318(n,k)), 0<=k<=n.

For primes p and k<p: T(p,k)=p (k>0), T(p+1,k)=p (k>1) and T(n,k)<p for n<p.

Mathematica

T[n_, k_] := FactorInteger[Binomial[n, k]][[-1, 1]];
Table[T[n, k], {n, 0, 13}, {k, 0, n}] // Flatten (* Jean-François Alcover, Sep 15 2021 *)

Crossrefs

Cf. A006530, A007318.

Sequence in context: A157694 A271187 A093557 * A048804 A158565 A132422

Adjacent sequences: A098799 A098800 A098801 * A098803 A098804 A098805

Keyword

nonn,tabl

Author

Reinhard Zumkeller, Nov 01 2004

Status

approved