The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A108323 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A108323

"Binary prime squares": squares whose binary expansions, read as decimal expansions, are primes.
(history; published version)

#16 by Joerg Arndt at Mon Sep 24 02:43:41 EDT 2018

STATUS

proposed

approved

#15 by Michel Marcus at Mon Sep 24 01:48:54 EDT 2018

STATUS

editing

proposed

#14 by Michel Marcus at Mon Sep 24 01:48:52 EDT 2018

CROSSREFS

Cf. A108322, A108324, A108325.

STATUS

proposed

editing

#13 by Jon E. Schoenfield at Sun Sep 23 23:50:43 EDT 2018

STATUS

editing

proposed

#12 by Jon E. Schoenfield at Sun Sep 23 23:50:40 EDT 2018

NAME

"Binary prime squares": perfect squares written in base 2 which, considered whose binary expansions, read as decimal numbers, expansions, are primes.

COMMENTS

Another definition: numbers having only digits 1 and 0, which, read in base 10 , are primes , and in base 2 are perfect squares. Derived from A108322 from which the 0-terms have been removed.

STATUS

approved

editing

#11 by Harvey P. Dale at Tue Jul 10 13:57:37 EDT 2012

STATUS

editing

approved

#10 by Harvey P. Dale at Tue Jul 10 13:57:34 EDT 2012

MATHEMATICA

fd2[n_]:=FromDigits[IntegerDigits[n, 2]]; fd2/@Select[Range[100300]^2, PrimeQ[fd2[#]]&](* Harvey P. Dale, Jul 10 2012 *)

#9 by Harvey P. Dale at Tue Jul 10 13:57:06 EDT 2012

MATHEMATICA

fd2[n_]:=FromDigits[IntegerDigits[#, n, 2]]&; fd2/@Select[Range[300100]^2, PrimeQ[ FromDigits[ IntegerDigitsfd2[#, 2]]]&] (* Harvey P. Dale, Jul 10 2012 *)

STATUS

approved

editing

#8 by Harvey P. Dale at Tue Jul 10 13:50:28 EDT 2012

STATUS

editing

approved

#7 by Harvey P. Dale at Tue Jul 10 13:50:23 EDT 2012

MATHEMATICA

FromDigits[IntegerDigits[#, 2]]&/@Select[Range[100300]^2, PrimeQ[ FromDigits[ IntegerDigits[#, 2]]]&] (* Harvey P. Dale, Jul 10 2012 *)