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 A274524 Numbers n such that both ror(n) and rol(n) are squares, where ror(x)=A038572(x) is x rotated one binary place to the right, rol(x)=A006257(x) is x rotated one binary place to the left. 1
 1, 2, 8, 32, 128, 512, 1568, 2048, 2312, 2592, 2888, 8192, 16928, 32768, 131072, 139392, 250632, 524288, 549152, 566048, 672800, 924800, 963272, 1318688, 2097152, 8388608, 8520192, 8769672, 9005768, 12261152, 13582472, 15635232, 33554432, 134217728, 136059008, 136587392 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A004171 and A081294 are subsequences. From Robert Israel, Jul 13 2016: (Start) All terms except 1 are even. Even terms are the numbers of the form n = (a+b)^2/8 such that for some d >= 1, 2^d <= n < 2^(d+1) and 2^(d+1)-1 = a*b. (End) LINKS Robert Israel, Table of n, a(n) for n = 1..10000 MAPLE F:= proc(d) local v, R, X;       v:= 2^(d+1)-1;       R:= select(t-> t^2 < v, numtheory:-divisors(v));       op(select(t -> t >= (v+1)/2 and t < v+1, map(t -> (t+ v/t)^2/8, R))); end proc: sort(convert({1, seq(F(i), i=1..50)}, list)); # Robert Israel, Jul 13 2016 MATHEMATICA Select[Range[10^6], Times @ Boole@ {IntegerQ@ Sqrt@ FromDigits[RotateRight@ #, 2], IntegerQ@ Sqrt@ FromDigits[RotateLeft@ #, 2]} &@ IntegerDigits[#, 2] == 1 &] (* Michael De Vlieger, Jun 29 2016 *) CROSSREFS Cf. A006257, A038572, A004171, A081294. Sequence in context: A282879 A217665 A320654 * A081294 A004171 A009117 Adjacent sequences:  A274521 A274522 A274523 * A274525 A274526 A274527 KEYWORD nonn,base AUTHOR Alex Ratushnyak, Jun 27 2016 STATUS approved

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Last modified October 22 01:38 EDT 2018. Contains 316431 sequences. (Running on oeis4.)