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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 Table of n, a(n) for n=1..6. 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 Cf. A000040, A112013. Sequence in context: A146658 A145440 A112013 * A154419 A208399 A097223 Adjacent sequences: A165688 A165689 A165690 * A165692 A165693 A165694 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.)