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A176406 Odd semiprimes minus 2. 0
7, 13, 19, 23, 31, 33, 37, 47, 49, 53, 55, 63, 67, 75, 83, 85, 89, 91, 93, 109, 113, 117, 119, 121, 127, 131, 139, 141, 143, 153, 157, 159, 167, 175, 181, 183, 185, 199, 201, 203, 207, 211, 213, 215, 217, 219, 233, 235, 245, 247, 251, 257, 263, 265, 285, 287 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..56.

FORMULA

a(n) = A046315(n) - 2.

MAPLE

isA001358 := proc(n) numtheory[bigomega](n) = 2 ; end proc: for n from 1 to 400 by 2 do if isA001358(n+2) then printf("%d, ", n) ; end if; end do: # R. J. Mathar, Apr 20 2010

MATHEMATICA

Select[Range[9, 301, 2], PrimeOmega[#]==2&]-2 (* Harvey P. Dale, May 11 2018 *)

CROSSREFS

Cf. A007921.

Sequence in context: A309649 A088982 A354460 * A033561 A227030 A049591

Adjacent sequences: A176403 A176404 A176405 * A176407 A176408 A176409

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Apr 16 2010

EXTENSIONS

Entries checked by R. J. Mathar, Apr 20 2010

STATUS

approved

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Last modified November 27 19:48 EST 2022. Contains 358406 sequences. (Running on oeis4.)