login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A361628 Sphenic numbers (products of 3 distinct primes) whose digits are primes. 0
222, 255, 273, 322, 357, 555, 777, 2222, 2233, 2235, 2255, 2337, 2355, 2373, 2522, 2553, 2555, 2737, 2755, 3237, 3322, 3333, 3335, 3355, 3522, 3535, 3553, 3723, 5222, 5235, 5253, 5322, 5335, 5522, 5523, 5555, 5727, 5735, 5757, 7222, 7257, 7322, 7337, 7527, 7535, 7553, 7557 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
Select[Flatten@ Table[FromDigits /@ Tuples[Prime[Range[4]], n], {n, 3, 4}], FactorInteger[#][[;; , 2]] == {1, 1, 1} &] (* Amiram Eldar, Mar 18 2023 *)
PROG
(PARI) isok(k) = (omega(k)==3) && (bigomega(k)==3) && !#select(x->!isprime(x), digits(k)); \\ Michel Marcus, Mar 21 2023
CROSSREFS
Intersection of A046034 and A007304.
Cf. A102782.
Sequence in context: A371423 A345521 A345775 * A101955 A063352 A250521
KEYWORD
nonn,base
AUTHOR
Massimo Kofler, Mar 18 2023
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 14 16:58 EDT 2024. Contains 374322 sequences. (Running on oeis4.)