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A085803
Semiprimes whose digits squared sum to a semiprime.
1
15, 34, 35, 51, 57, 74, 91, 95, 121, 122, 123, 129, 134, 142, 143, 155, 161, 169, 183, 209, 213, 214, 218, 219, 221, 235, 237, 247, 253, 265, 274, 291, 299, 301, 305, 314, 319, 321, 323, 326, 327, 329, 334, 341, 361, 362, 381, 382, 391, 394, 395, 403, 407
OFFSET
1,1
LINKS
MATHEMATICA
Select[Range[500], PrimeOmega[#]==PrimeOmega[Total[IntegerDigits[#]^2]] == 2&] (* Harvey P. Dale, Oct 03 2012 *)
PROG
(PARI) isok(k)={bigomega(k)==2 && bigomega(norml2(digits(k)))==2} \\ Andrew Howroyd, Sep 18 2024
CROSSREFS
Intersection of A001358 and A217907.
Sequence in context: A242243 A219855 A270072 * A168573 A139578 A345733
KEYWORD
base,nonn
AUTHOR
Jason Earls, Jul 24 2003
EXTENSIONS
Offset changed by Andrew Howroyd, Sep 18 2024
STATUS
approved