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A023113 Numbers n such that n remains square when digit 6 is appended. 0
1, 25, 1849, 36481, 2666689, 52606009, 3845364121, 75857828929, 5545012396225, 109386936710041, 7995904029992761, 157735886878050625, 11530088066237165569, 227455039491212291641, 16626378995609962758169 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The terms of the sequence are the squares of the y-values in the solution to the Pellian equation x^2-10*y^2=6. - Colin Barker, Sep 28 2013

LINKS

Table of n, a(n) for n=1..15.

FORMULA

Empirical G.f.: -x*(x^4+24*x^3+382*x^2+24*x+1) / ((x-1)*(x^2-38*x+1)*(x^2+38*x+1)). [Colin Barker, Jan 31 2013]

CROSSREFS

Sequence in context: A212333 A187404 A172261 * A322247 A177837 A056047

Adjacent sequences:  A023110 A023111 A023112 * A023114 A023115 A023116

KEYWORD

nonn,base

AUTHOR

David W. Wilson

STATUS

approved

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Last modified January 22 05:11 EST 2019. Contains 319353 sequences. (Running on oeis4.)