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A168139 Squares whose sum and number of digits are also squares. 0
0, 1, 4, 9, 1521, 1681, 2025, 2304, 2601, 3364, 3481, 3600, 4489, 4624, 5776, 5929, 7225, 7396, 8100, 8836, 9025, 100000000, 100020001, 100040004, 100060009, 100080016, 100100025, 100200100, 100220121, 100240144, 100260169, 100400400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

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

EXAMPLE

1521=39^2, number of digits = 4, number of digits = 1+5+2+1=9.

PROG

(PARI) isok(n) = issquare(n) && issquare(sumdigits(n)) && issquare(length(Str(n))); \\ Michel Marcus, Oct 15 2013

CROSSREFS

Subsequence of A053057 (with additional first term = 0).

Sequence in context: A028869 A179935 A073172 * A258660 A260305 A229338

Adjacent sequences:  A168136 A168137 A168138 * A168140 A168141 A168142

KEYWORD

base,nonn

AUTHOR

Zak Seidov, Nov 19 2009

STATUS

approved

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Last modified December 9 00:32 EST 2019. Contains 329871 sequences. (Running on oeis4.)