A108230 a(1) = 0, a(n) = order of prime A088387(n).

0, 1, 2, 1, 3, 2, 4, 1, 2, 3, 5, 1, 6, 4, 3, 1, 7, 2, 8, 3, 4, 5, 9, 1, 3, 6, 2, 4, 10, 3, 11, 1, 5, 7, 4, 2, 12, 8, 6, 1, 13, 4, 14, 5, 2, 9, 15, 1, 4, 3, 7, 6, 16, 2, 5, 1, 8, 10, 17, 3, 18, 11, 2, 1, 6, 5, 19, 7, 9, 4, 20, 2, 21, 12, 3, 8, 5, 6, 22

Offset

1,3

Links

Table of n, a(n) for n=1..79.

Example

a(12) = 1 because 2^2 is the largest prime power (yet not the power of the largest prime) dividing 12 and 2 is the first prime.

Mathematica

a = {0}; For[n = 2, n < 80, n++, max = 0; b = FactorInteger[n]; For[j = 1, j < Length[b] + 1, j++, If[b[[j, 1]]^b[[j, 2]] > max, max = b[[j, 1]]^b[[j, 2]]]]; AppendTo[a, PrimePi[FactorInteger[max][[1, 1]]]]]; a (* Stefan Steinerberger, Oct 24 2007 *)

Crossrefs

Cf. A088387, A034699.

Sequence in context: A367587 A363942 A363487 * A334202 A324729 A355532

Adjacent sequences: A108227 A108228 A108229 * A108231 A108232 A108233

Keyword

nonn

Author

Leroy Quet, Jun 16 2005

Extensions

More terms from Stefan Steinerberger, Oct 24 2007

Status

approved