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A112770 Products of pairs of terms from A003627. 1
4, 10, 22, 25, 34, 46, 55, 58, 82, 85, 94, 106, 115, 118, 121, 142, 145, 166, 178, 187, 202, 205, 214, 226, 235, 253, 262, 265, 274, 289, 295, 298, 319, 334, 346, 355, 358, 382, 391, 394, 415, 445, 451, 454, 466, 478, 493, 502, 505, 514, 517, 526, 529, 535 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

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

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.

LINKS

Eric Weisstein's World of Mathematics, Eisenstein Integer.

Eric Weisstein's World of Mathematics, Eisenstein Prime.

Eric Weisstein's World of Mathematics, Semiprime.

FORMULA

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

CROSSREFS

Cf. A001358, A003627.

Sequence in context: A111927 A109885 A054211 * A112774 A008178 A009891

Adjacent sequences:  A112767 A112768 A112769 * A112771 A112772 A112773

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com) and Ray Chandler (rayjchandler(AT)sbcglobal.net), Oct 15 2005

EXTENSIONS

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

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Last modified February 13 04:08 EST 2012. Contains 205435 sequences.