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A133447 Nonsemiprime hyperperfect numbers. 1
325, 2133, 10693, 16513, 19521, 51301, 159841, 176661, 214273, 306181, 1433701, 1570153, 1950625, 2469601, 2924101, 5199013, 9398593, 10445221, 15407173, 23548753, 28600321, 39147301, 60110701, 62722153, 88347781, 112803841 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The other 25 of the first 35 values of A007592 are all semiprimes A001358.

LINKS

Donovan Johnson, Table of n, a(n) for n = 1..192 (terms < 10^12)

FORMULA

A100959 INTERSECTION A007592.

EXAMPLE

a(1) = 325 = 5^2 * 13.

a(2) = 2133 = 3^3 * 79.

a(3) = 10693 = 17^2 * 37.

a(4) = 16513 = 7^2 * 337.

a(5) = 19521 = 3^4 * 341.

a(6) = 51301 = 29^2 * 61.

a(7) = 159841 = 11^2 * 1321.

a(8) = 176661 = 3^5 * 727.

a(9) = 214273 = 47^2 * 97.

a(10) = 306181 = 53^2 * 109.

MAPLE

a034897 := [] : fd := fopen("b034897.txt", READ) : bf := fscanf(fd, "%d %d") : while nops(bf) <> 0 do a034897 := [op(a034897), op(2, bf) ] ; bf := fscanf(fd, "%d %d") ; od: a007592 := [] : for n in a034897 do m := (n-1)/( numtheory[sigma](n)-n-1) ; if m > 1 then a007592 := [op(a007592), n] ; fi ; od: isA100959 := proc(n) if numtheory[bigomega](n) <> 2 then true ; else false ; end: end: for n in a007592 do if isA100959(n) then printf("%d, ", n) ; fi ; od: # R. J. Mathar, Jan 08 2008

CROSSREFS

Cf. A001358, A007592, A100959.

Sequence in context: A183645 A299708 A031714 * A179535 A145414 A298106

Adjacent sequences:  A133444 A133445 A133446 * A133448 A133449 A133450

KEYWORD

nonn

AUTHOR

Jonathan Vos Post, Dec 22 2007

EXTENSIONS

More terms from R. J. Mathar, Jan 08 2008

STATUS

approved

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Last modified December 3 11:13 EST 2021. Contains 349462 sequences. (Running on oeis4.)