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A046710 Irrational unitary-phi amicable numbers. 1
26640, 1038960, 1651680, 64415520, 7246080, 282597120, 844592855040, 32939121346560, 476734095360, 18592629719040, 124972029225861120, 486048526115143680, 2047588591705018859520, 79855955076495735521280 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,1

COMMENTS

Two numbers a and b are called irrational unitary-phi amicable numbers if they satisfy uphi(a)=uphi(b)=2*(a^2-b^2)^(1/2) where if x=Product p(i)^r(i) then uphi(x)=Product (p(i)^r(i)-1) (A047994).

Factorizations: 2^4*3^2*5*37, 2^4*3^3*13*5*37, 2^5*3^2*31*5*37, 2^5*3^3*13*31*5*37, ...

LINKS

Table of n, a(n) for n=4..17.

CROSSREFS

Cf. A046709.

Sequence in context: A236622 A329785 A229592 * A251303 A196937 A253292

Adjacent sequences:  A046707 A046708 A046709 * A046711 A046712 A046713

KEYWORD

nonn

AUTHOR

Yasutoshi Kohmoto

STATUS

approved

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Last modified July 9 16:50 EDT 2020. Contains 335545 sequences. (Running on oeis4.)