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A023112 Numbers n such that n remains square when digit 4 is appended. 1
0, 144, 207936, 299843856, 432374632704, 623483920515600, 899063381008862784, 1296448771930859619216, 1869478230060918562046976, 2695786311299072635612120464, 3887321991415032679634115662400 (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=4. - Colin Barker, Sep 28 2013

LINKS

Table of n, a(n) for n=1..11.

FORMULA

Empirical G.f.: -144*x^2*(x+1) / ((x-1)*(x^2-1442*x+1)). [Colin Barker, Jan 31 2013]

A023112(n) = 4*A023111(n). [Colin Barker, Sep 28 2013]

CROSSREFS

Sequence in context: A221124 A008700 A047807 * A159424 A013751 A033514

Adjacent sequences:  A023109 A023110 A023111 * A023113 A023114 A023115

KEYWORD

nonn,base

AUTHOR

David W. Wilson

STATUS

approved

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Last modified December 15 22:36 EST 2018. Contains 318155 sequences. (Running on oeis4.)