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A260477 Numbers n where n^2 is an anagram of (n+1)^2 in base 2. 1
9, 17, 33, 49, 50, 65, 73, 77, 85, 86, 97, 106, 129, 137, 149, 157, 161, 165, 178, 186, 193, 201, 212, 213, 225, 226, 257, 265, 273, 279, 281, 285, 300, 305, 307, 310, 317, 321, 325, 332, 334, 345, 355, 365, 366, 378, 385, 393, 394, 413, 426, 427, 449, 469 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Base 2 equivalent of A072841.

It appears that one of these numbers has a 1/n chance of being divisible by an odd number n, but a smaller than 1/n chance if n is even.

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

EXAMPLE

17 is a term of the sequence because its square base 2 (100100001) and 18's square base 2 (101000100) are anagrams.

MATHEMATICA

For[i = 1, i <= 10000, i++,

If[Sort[IntegerDigits[i^2, 2]] == Sort[IntegerDigits[(i + 1)^2, 2]],

  Print[i]]]

PROG

(PARI) is(n)=hammingweight(n^2)==hammingweight((n+1)^2) && #binary(n^2)==#binary((n+1)^2) \\ Charles R Greathouse IV, Aug 29 2015

CROSSREFS

Sequence in context: A090994 A164887 A328016 * A275543 A111733 A127193

Adjacent sequences:  A260474 A260475 A260476 * A260478 A260479 A260480

KEYWORD

base,easy,nonn

AUTHOR

Dhilan Lahoti, Aug 28 2015

EXTENSIONS

a(27)-a(54) from Charles R Greathouse IV, Aug 29 2015

STATUS

approved

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Last modified January 24 10:24 EST 2020. Contains 331193 sequences. (Running on oeis4.)