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A112392 Squares of the form 3*semiprime(n) - 2. 2
16, 25, 64, 100, 169, 256, 361, 400, 529, 625, 676, 784, 961, 1156, 1444, 2116, 2209, 3136, 3721, 3844, 4096, 4489, 5041, 5929, 7744, 7921, 8281, 9604, 10000, 10201, 11236, 11449, 11881, 12100, 13456, 14641, 16129, 16384, 17161, 18496, 20164 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..41.

MATHEMATICA

Select[3#-2&/@Select[Range[7000], PrimeOmega[#]==2&], IntegerQ[ Sqrt[#]]&] (* Harvey P. Dale, Jun 22 2011 *)

PROG

(PARI) for(i=1, 15000, if(bigomega(i)==2&&issquare(3*i-2), print1(3*i-2, ", "))) (Herrgesell)

CROSSREFS

Cf. A112393.

Sequence in context: A118489 A110922 A065408 * A109685 A188826 A152152

Adjacent sequences:  A112389 A112390 A112391 * A112393 A112394 A112395

KEYWORD

nonn

AUTHOR

Giovanni Teofilatto, Dec 05 2005

EXTENSIONS

More terms from Lambert Herrgesell (zero815(AT)googlemail.com), Dec 12 2005

STATUS

approved

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Last modified December 8 18:37 EST 2019. Contains 329865 sequences. (Running on oeis4.)