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A230095 Odious numbers (A000069) that are the product of exactly two distinct primes. 3
14, 21, 22, 26, 35, 38, 55, 62, 69, 74, 82, 87, 91, 93, 94, 115, 118, 122, 133, 134, 143, 145, 146, 155, 158, 161, 185, 194, 203, 205, 206, 213, 214, 217, 218, 247, 253, 254, 259, 262, 265, 274, 295, 299, 301, 302, 309, 314, 319, 321, 327, 334, 339, 341, 346 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

E. Fouvry, C. Mauduit, Sommes des chiffres et nombres presque premiers, (French) [Sums of digits and almost primes] Math. Ann. 305 (1996), no. 3, 571--599. MR1397437 (97k:11029).

PROG

(PARI) isodious(n)=b = binary(n); sum(i=1, #b, b[i]==1) % 2;

isok(n) = isodious(n) && (bigomega(n)==2) && (omega(n)==2); \\ Michel Marcus, Oct 12 2013

(PARI) list(lim)=my(v=List()); forprime(p=2, lim\2, forprime(q=2, min(lim\p, p-1), if(hammingweight(p*q)%2, listput(v, p*q)))); Set(v) \\ Charles R Greathouse IV, Jan 31 2017

CROSSREFS

Cf. A000069, A027697, A130593.

Sequence in context: A028395 A167170 A213536 * A133185 A013629 A234802

Adjacent sequences:  A230092 A230093 A230094 * A230096 A230097 A230098

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Oct 11 2013

EXTENSIONS

More terms from Michel Marcus, Oct 12 2013

STATUS

approved

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Last modified October 22 14:44 EDT 2019. Contains 328318 sequences. (Running on oeis4.)