challenge for programmable calculators

[Gerson W. Barbosa]

[quote= A non-brute-force solution would greatly enlighten this rainy day.
[/quote]

I hope the rain has gone :-)

%%HP: T(3)A(D)F(.);
\<< 1. 9.
FOR a 1. 9.
FOR b a SQ b * a b SQ * + 1. - NEG DUP SQ a b * 4. * a 100. * b 10. * + * + \v/ + a b * 2. * / DUP FP NOT NOT { DROP } { DUP 10. < { a 100. * b 10. * + + } { DROP } IFTE } IFTE
NEXT
NEXT
\>>

EVAL -->

135.
144.

after 2.9 seconds (hp 50g)