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%I #14 Aug 20 2017 10:54:22
%S 8,35,783,8835,92415,956483,9634815,95413823,941385123,9857511224,
%T 99575589135,993574355523,9553625719235,99581119573155,
%U 992553557213123,9535746315113315,96113351543713155,993511252251119715,9611213651115713535,93112315591271511615,963115211115325173135,9621111711335151513615,91735112131113523151523
%N Largest n-digit number k such that k+1 as well as 1 + the product of digits of k are squares greater than 1.
%p readlib(issqr): Digits:=100: for d from 1 to 15 do for n from floor(sqrt(10^d)) by -1 to ceil(sqrt(10^(d-1)+1)) do m:=mul(j,j=convert(n^2-1,base,10)): if m<>0 and issqr(m+1) then printf("%d, ",n^2-1): break fi od od: # C. Ronaldo
%Y Cf. A081990, A089697.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Nov 10 2003
%E More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 25 2004
%E Definition clarified by _Chai Wah Wu_, Aug 14 2017
%E a(17) from _Chai Wah Wu_, Aug 16 2017
%E a(18)-a(23) from _Chai Wah Wu_, Aug 19 2017
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