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A272711 Square numbers whose binary reversal is also square. 0
1, 4, 9, 16, 36, 64, 144, 256, 576, 1024, 2304, 4096, 9216, 16384, 36864, 65536, 147456, 262144, 589824, 1048576, 2359296, 4194304, 9437184, 16777216, 20457529, 37748736, 67108864, 81830116, 143784081, 150994944, 268435456, 327320464, 331130809, 575136324, 603979776 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The first term in this sequence whose binary reversal is not 1 or 9 is 20457529 (which is a binary palindrome).

The previous comment means that the sequence does not just contain the squares of numbers in A029744. - R. J. Mathar, May 06 2016

LINKS

Table of n, a(n) for n=1..35.

MATHEMATICA

Select[Range[10^5]^2, IntegerQ@ Sqrt@ FromDigits[ Reverse@ IntegerDigits[#, 2], 2] &] (* Giovanni Resta, May 05 2016 *)

PROG

(PARI) lista(nn) = {for (n=1, nn, if (issquare(subst(Polrev(binary(n^2)), x, 2)), print1(n^2, ", ")); ); } \\ Michel Marcus, May 05 2016

CROSSREFS

Cf. A000290, A030101, A029983, A229687.

Cf. A061457 (analogous in base 10).

Sequence in context: A025620 A117218 A226076 * A018228 A204503 A138858

Adjacent sequences:  A272708 A272709 A272710 * A272712 A272713 A272714

KEYWORD

nonn,base

AUTHOR

Benjamin Przybocki, May 04 2016

STATUS

approved

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Last modified November 14 02:19 EST 2019. Contains 329108 sequences. (Running on oeis4.)