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A176525 Fermi-Dirac semiprimes: products of two distinct terms of A050376 3
6, 8, 10, 12, 14, 15, 18, 20, 21, 22, 26, 27, 28, 32, 33, 34, 35, 36, 38, 39, 44, 45, 46, 48, 50, 51, 52, 55, 57, 58, 62, 63, 64, 65, 68, 69, 74, 75, 76, 77, 80, 82, 85, 86, 87, 91, 92, 93, 94, 95, 98, 99, 100, 106, 111, 112, 115, 116, 117, 118, 119, 122 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The sequence essentially differs from A000379 beginning with a(108)=212 (not 210). All squarefree terms of A001358 are in the sequence. The sequence essentially differs also from A064176 which contains products of even distinct terms of A050376

REFERENCES

S. Litsyn and V. S. Shevelev, On factorization of integers with restrictions on the exponent, INTEGERS: Electronic Journal of Combinatorial Number Theory, 7 (2007), #A33, 1-36.

V. S. Shevelev, Multiplicative functions in the Fermi-Dirac arithmetic, Izvestia Vuzov of the North-Caucasus region, Nature sciences 4 (1996), 28-43 [Russian].

LINKS

Table of n, a(n) for n=1..62.

FORMULA

If a(n)=u*v, u<v, u,v are distinct terms of A050376 "Fermi-Dirac primes", then A064380(a(n))=a(n)-u-v+1+Sum{i>=1}(-1)^(i-1)*floor(v/u^i).

CROSSREFS

Cf. A001358 A050376 A000379 A176472 A176509 A064380 A050292

Cf. A064176. [From R. J. Mathar, Apr 29 2010]

Sequence in context: A131181 A064176 A000379 * A065985 A233421 A060652

Adjacent sequences:  A176522 A176523 A176524 * A176526 A176527 A176528

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Apr 19 2010, Apr 20 2010

STATUS

approved

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Last modified April 18 03:01 EDT 2014. Contains 240688 sequences.