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A165691 Primes p such that pi(p) is the product of the first digit of p and the rest of the number. 0
17, 73, 619, 2077121, 5070613, 503890508623 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
A subsequence of A112013. There is no further term up to 3*10^10.
a(7) > 2.07*10^12. - Giovanni Resta, Feb 27 2013
a(7) > 10^17. - Chai Wah Wu, Apr 15 2021
LINKS
EXAMPLE
619=prime(6*19), so 619 is in the sequence.
MATHEMATICA
Do[If[h=IntegerDigits[Prime[m]]; m==h[[1]]*FromDigits[Delete[h, 1]],
Print[Prime[m]}]], {m, 355000}]
CROSSREFS
Sequence in context: A146658 A145440 A112013 * A154419 A208399 A097223
KEYWORD
hard,more,nonn,base
AUTHOR
Farideh Firoozbakht, Oct 14 2009
EXTENSIONS
a(6) from Giovanni Resta, Feb 27 2013
STATUS
approved

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Last modified July 21 06:08 EDT 2024. Contains 374463 sequences. (Running on oeis4.)