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%I #19 Apr 22 2022 12:08:32
%S 6,11,14,20,25,35,39,59,76,84,85,92,94,95,96,104,105,108,116,123,125,
%T 129,133,136,147,153,157,160,169,174,181,186,189,190,192,194,195,198,
%U 200,206,207,231,232,238,239,248,256,270,274,279,283,288,293,302,304,307,309,323,326,332,340,344,346,350,360,361,363,370,371,377,385,391,398,399
%N Square roots of perfect squares which are sum of two nonzero pentagonal numbers (A333007).
%H Peter Kagey, <a href="/A333008/b333008.txt">Table of n, a(n) for n = 1..1000</a>
%e a(7) = 39. a(7)^2 = 1521 = 1 + 1520.
%t Take[Union[Select[Sqrt[#]&/@(Total/@Tuples[PolygonalNumber[ 5,Range[ 400]],2]),IntegerQ]],80] (* _Harvey P. Dale_, Apr 22 2022 *)
%Y Cf. A333007 (squares), A333009 (successive differences).
%Y Cf. A000326 (pentagonal numbers).
%K nonn
%O 1,1
%A _Olivier Gérard_, Mar 05 2020