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A108322 "Binary prime squares": a(n) = n^2 written in base 2 and interpreted as a base-10 number, if that number is prime; a(n) = 0 otherwise. 3

%I

%S 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1101001001,0,

%T 0,0,0,0,0,0,0,0,10111110001,0,0,0,0,0,0,0,0,0,0,0,101000101001,0,

%U 101011111001,0,0,0,0,0,0,0,0,0,0,0,0,0,1000110001001,0,0,0,0,0,0,0,0,0

%N "Binary prime squares": a(n) = n^2 written in base 2 and interpreted as a base-10 number, if that number is prime; a(n) = 0 otherwise.

%C Another definition: numbers having only digits 1 and 0, which, read in base 10 are primes and in base 2 are perfect squares.

%e a(5)=0 because 5^2 = 25 = 11001_2, and the decimal number 11001 is not prime.

%e a(29)=1101001001 because 29^2 = 841 = 1101001001_2, and the decimal number 1101001001 is prime.

%Y Cf. A108323, A108324, A108325.

%K easy,nonn,base

%O 1,29

%A _Alexandre Wajnberg_, Jun 30 2005

%E Edited by _Jon E. Schoenfield_, Sep 23 2018

%E Offset corrected by _Michel Marcus_, Sep 24 2018

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Last modified January 25 03:49 EST 2020. Contains 331241 sequences. (Running on oeis4.)