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A071686 Smallest solution to gcd(x, Rev(x)) = 2^n. 11
2, 4, 8, 2192, 21920, 291008, 610688, 2112256, 2131456, 2937856, 25329664, 230465536, 694018048, 2344321024, 4688642048, 2112421888, 65012891648, 650128916480, 4494196736, 63769149440, 637691494400, 23842827272192, 276298064723968, 420127895977984, 4897795987210240 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..32

FORMULA

a(n) = A069554(2^n).

MATHEMATICA

a[n_] := Block[{k = 2^n}, While[GCD[k, FromDigits@ Reverse@ IntegerDigits@ k] != 2^n, k += 2^n]; k]; Array[a, 17] (* Giovanni Resta, Nov 14 2019 *)

CROSSREFS

Cf. A004086, A055483, A069554, A072005, A072021, A072050.

Sequence in context: A067499 A135212 A012456 * A296742 A103097 A335750

Adjacent sequences:  A071683 A071684 A071685 * A071687 A071688 A071689

KEYWORD

nonn,base

AUTHOR

Labos Elemer, Jun 03 2002

EXTENSIONS

a(22)-a(25) from Giovanni Resta, Oct 29 2019

STATUS

approved

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Last modified May 17 15:14 EDT 2021. Contains 343979 sequences. (Running on oeis4.)