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%I #21 Jul 11 2023 09:12:44
%S 2,4,13,57,64,349
%N Numbers k such that A300570(k) considered simply as a decimal string is prime.
%H <a href="/index/Mo#MWP">Index entries for sequences related to Most Wanted Primes video</a>
%e A300570(4) = 10011101 = A000040(665267) is prime, so 4 is a term.
%e A300570(5) = 10110011101 = 6389*1582409 is composite, so 5 is not a term.
%t Select[Range[350], PrimeQ[FromDigits[Flatten[IntegerDigits[Range[#, 1, -1], 2]]]] &] (* _Amiram Eldar_, Feb 19 2023 *)
%o (Python)
%o from sympy import isprime
%o from itertools import count, islice
%o def agen(): # generator of terms
%o s = ""
%o for k in count(1):
%o s = bin(k)[2:] + s
%o if isprime(int(s)): yield k
%o print(list(islice(agen(), 5))) # _Michael S. Branicky_, Feb 19 2023
%Y Cf. A300570, A098780 (A300570 converted to base 10), A348792 (primes in A098780).
%K nonn,base,more
%O 1,1
%A _N. J. A. Sloane_, Feb 19 2023
%E a(6) from _Alois P. Heinz_, Feb 19 2023
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