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A068075 Lesser of a primitive pair such that n and its 10's complement are simultaneously square. 1
1, 36, 324, 123904, 3968064, 28901376, 14997431296, 434207195136, 2552428007424, 1780607738773504 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

If k is in the sequence so is k * 100^m.

LINKS

Table of n, a(n) for n=1..10.

MATHEMATICA

Do[ If[n^2 <= 5*10^Floor[ Log[10, n^2]] && IntegerQ[ Sqrt[ 10^Floor[ Log[10, n^2] + 1] - n^2]] && Take[ IntegerDigits[n^2], -1] != {0}, Print[n^2]], {n, 1, 4*10^6}]

CROSSREFS

Cf. A068810.

Sequence in context: A213124 A067473 A223299 * A219004 A053136 A000821

Adjacent sequences:  A068072 A068073 A068074 * A068076 A068077 A068078

KEYWORD

base,nonn

AUTHOR

Robert G. Wilson v, Mar 20 2002

STATUS

approved

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Last modified December 5 13:26 EST 2019. Contains 329751 sequences. (Running on oeis4.)