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A112381 Zero-free semiprimes. 1
4, 6, 9, 14, 15, 21, 22, 25, 26, 33, 34, 35, 38, 39, 46, 49, 51, 55, 57, 58, 62, 65, 69, 74, 77, 82, 85, 86, 87, 91, 93, 94, 95, 111, 115, 118, 119, 121, 122, 123, 129, 133, 134, 141, 142, 143, 145, 146, 155, 158, 159, 161, 166, 169, 177, 178, 183, 185, 187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A001358 and A052382. - Michel Marcus, Oct 09 2013

LINKS

Table of n, a(n) for n=1..59.

EXAMPLE

74 is in the sequence because it is a semiprime (2*37) and does not have 0 in digits. - Michel Marcus, Oct 14 2013

MATHEMATICA

SemiPrimeQ[n_Integer] := If[Abs[n] < 2, False, (2 == Plus @@ Transpose[FactorInteger[Abs[n]]][[2]])]; Select[Range[2, 200], SemiPrimeQ[#] && Min[IntegerDigits[#]] > 0 &] (* T. D. Noe, Oct 11 2013 *)

PROG

(PARI) lista(nn) = {vec = vector(nn, i, i); pp = select(i->(((bigomega(i) == 2) && vecmin(digits(i)))), vec); print(pp); } \\ Michel Marcus, Oct 09 2013

CROSSREFS

Sequence in context: A120134 A241451 A288379 * A182150 A108634 A135355

Adjacent sequences:  A112378 A112379 A112380 * A112382 A112383 A112384

KEYWORD

base,nonn

AUTHOR

Zak Seidov, May 30 2006

EXTENSIONS

Data corrected by Michel Marcus, Oct 14 2013

STATUS

approved

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Last modified March 19 17:21 EDT 2019. Contains 321330 sequences. (Running on oeis4.)