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 A242756 Semiprimes having only the curved digits. 1
 6, 9, 22, 25, 26, 33, 35, 38, 39, 55, 58, 62, 65, 69, 82, 85, 86, 93, 95, 202, 203, 205, 206, 209, 226, 235, 253, 259, 262, 265, 289, 295, 298, 299, 302, 303, 305, 309, 323, 326, 329, 335, 339, 355, 358, 362, 365, 382, 386, 393, 395, 398, 502, 505, 526, 529, 533 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A curved-digit semiprime has only the curved digits, i.e., 0, 2, 3, 5, 6, 8 or 9. LINKS K. D. Bajpai, Table of n, a(n) for n = 1..3484 EXAMPLE 358 = 2 * 179 is semiprime having only the curved digits 3, 5 and 8. Hence appears in the sequence. 689 = 13 * 53 is semiprime having only the curved digits 6, 8 and 9. Hence appears in the sequence. MATHEMATICA A242756 = {}; Do[a = PrimeOmega[n]; If[a == 2 && Intersection[IntegerDigits[n], {1, 4, 7}] == {}, AppendTo[A242756, n]], {n, 1000}]; A242756 PROG (PARI) s=[]; for(n=1, 600, if(bigomega(n)==2 && setintersect(vecsort(digits(n), , 8), [1, 4, 7])==[], s=concat(s, n))); s \\ Colin Barker, Jun 03 2014 CROSSREFS Cf. A028374, A001358, A034470. Sequence in context: A165717 A239874 A043103 * A268665 A043883 A112393 Adjacent sequences: A242753 A242754 A242755 * A242757 A242758 A242759 KEYWORD nonn,base AUTHOR K. D. Bajpai, May 22 2014 STATUS approved

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Last modified August 11 01:05 EDT 2024. Contains 375059 sequences. (Running on oeis4.)