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A121307 Products of three terms from A003627. 0
8, 20, 44, 50, 68, 92, 110, 116, 125, 164, 170, 188, 212, 230, 236, 242, 275, 284, 290, 332, 356, 374, 404, 410, 425, 428, 452, 470, 506, 524, 530, 548, 575, 578, 590, 596 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

It would be incorrect to call these Eisenstein 3-almost primes. For the Eisenstein primes see A055664. - N. J. A. Sloane (njas(AT)research.att.com), Feb 06 2008.

REFERENCES

Conway, J. H. and Guy, R. K., The Book of Numbers. New York: Springer-Verlag, pp. 220-223, 1996.

Wagon, S. "Eisenstein Primes." Section 9.8 in Mathematica in Action. New York: W. H. Freeman, pp. 319-323, 1991.

FORMULA

{a(n)} = {p*q*r: p and q and r elements of A007645} = {p*q*r: p and q and r of form 3*m^2 * n^2 for integers m, n}

CROSSREFS

Cf. A003627, A014612, A112770.

Sequence in context: A086062 A006416 A192753 * A086169 A169878 A107816

Adjacent sequences:  A121304 A121305 A121306 * A121308 A121309 A121310

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com), Sep 05 2006

EXTENSIONS

Definition corrected by N. J. A. Sloane (njas(AT)research.att.com), Feb 06 2008

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Last modified February 17 19:13 EST 2012. Contains 206085 sequences.