A242756 Semiprimes having only the curved digits.

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

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