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A068176
a(1) = 2; for n>1, a(n) is the smallest square > a(n-1) obtained by inserting digits into a(n-1).
5
2, 25, 225, 1225, 13225, 133225, 10336225, 1033622500, 103362250000, 10336225000000, 1033622500000000, 103362250000000000, 10336225000000000000, 1033622500000000000000, 103362250000000000000000
OFFSET
1,1
EXAMPLE
a(2) = 25. hence a(3) = 225 the smallest square formed from 25.
CROSSREFS
Cf. A068175, A091875 gives square roots.
Sequence in context: A203767 A206392 A074438 * A131585 A042919 A229975
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Feb 25 2002
EXTENSIONS
Corrected and extended by Ray Chandler, Oct 11 2003
STATUS
approved