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A108322 "Binary prime squares": perfect squares n^2 written in base 2 which, considered as decimal numbers, are primes; 0 if no such "binary prime square" exists. 1
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, 0, 0, 0, 0, 0, 0, 0, 0, 10111110001, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 101000101001, 0, 101011111001, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1000110001001, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,29

COMMENTS

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

LINKS

Table of n, a(n) for n=0..75.

EXAMPLE

a(5)=0 because 5^2=25(b10)=11001(b2), which read as the decimal number 11,001 is not prime.

a(29)=1101001001 because 29^2=841(b10)=1101001001, which read as the decimal 1101001001 is prime.

CROSSREFS

Sequence in context: A134595 A217610 A219319 * A108323 A154474 A096553

Adjacent sequences:  A108319 A108320 A108321 * A108323 A108324 A108325

KEYWORD

easy,nonn,base

AUTHOR

Alexandre Wajnberg, Jun 30 2005

STATUS

approved

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Last modified August 18 14:29 EDT 2017. Contains 290720 sequences.