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A108230 a(1) = 0, a(n) = order of prime A088387(n). 0
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 (list; graph; refs; listen; history; text; internal format)
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: A243561 A135550 A035491 * A061395 A156061 A225395

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

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Last modified August 29 08:27 EDT 2014. Contains 246187 sequences.