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A130064 (n / SmallestPrimeFactor(n)) * GreatestPrimeFactor(n). 7
1, 2, 3, 4, 5, 9, 7, 8, 9, 25, 11, 18, 13, 49, 25, 16, 17, 27, 19, 50, 49, 121, 23, 36, 25, 169, 27, 98, 29, 75, 31, 32, 121, 289, 49, 54, 37, 361, 169, 100, 41, 147, 43, 242, 75, 529, 47, 72, 49, 125, 289, 338, 53, 81, 121, 196, 361, 841, 59, 150, 61, 961, 147, 64, 169, 363 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) = n*A006530(n)/A020639(n) = A032742(n)*A006530(n);

a(n)>=n; a(n)=n iff n is a prime power: a(A000961(n))=A000961(n);

a(A001221(n)) <= A001221(n); a(A001222(n)) = A001222(n);

a(n) = A130065(n)+n*A046665(n)*A074320(n)/A066048(n) = A000290(n)/A130065(n).

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..10000

CROSSREFS

Sequence in context: A241916 A079871 A273291 * A273285 A068795 A222257

Adjacent sequences:  A130061 A130062 A130063 * A130065 A130066 A130067

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 05 2007

STATUS

approved

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Last modified October 18 01:01 EDT 2018. Contains 316297 sequences. (Running on oeis4.)