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A081811 If n = p_1^e_1 * ... * p_k^e_k, p_1 < ... < p_k primes, then a(n) = min{ p_i*e_i }. 0
0, 2, 3, 4, 5, 2, 7, 6, 6, 2, 11, 3, 13, 2, 3, 8, 17, 2, 19, 4, 3, 2, 23, 3, 10, 2, 9, 4, 29, 2, 31, 10, 3, 2, 5, 4, 37, 2, 3, 5, 41, 2, 43, 4, 5, 2, 47, 3, 14, 2, 3, 4, 53, 2, 5, 6, 3, 2, 59, 3, 61, 2, 6, 12, 5, 2, 67, 4, 3, 2, 71, 6, 73, 2, 3, 4, 7, 2, 79, 5, 12, 2, 83, 3, 5, 2, 3, 6, 89, 2, 7, 4, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..93.

PROG

(PARI) a(n)=local(f); if(n<1, 0, f=factor(n); vecmin(vector(matsize(f)[1], k, f[k, 1]*f[k, 2])))

CROSSREFS

Sequence in context: A223490 A244734 A230089 * A034684 A028233 A216972

Adjacent sequences:  A081808 A081809 A081810 * A081812 A081813 A081814

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Apr 10 2003

STATUS

approved

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Last modified February 17 20:22 EST 2018. Contains 299296 sequences. (Running on oeis4.)