OFFSET
1,2
COMMENTS
There are 325 terms below 10^200, with the largest one having 83 decimal digits. - Max Alekseyev, May 31 2018
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..325
MAPLE
P:=proc(n) local i, k, w; for i from 1 by 1 to n do w:=1; k:=i; while k>0 do w:=w*(k-(trunc(k/10)*10))^2; k:=trunc(k/10); od; if w>0 then if trunc(w/i)=w/i then print(i); fi; fi; od; end: P(1000000);
MATHEMATICA
fQ[n_] := Block[{d = Times @@ (IntegerDigits[n]^2)}, And[d != 0, Mod[d, n] == 0]]; Select[Range@ 1000000, fQ] (* Michael De Vlieger, Apr 29 2015 *)
PROG
(PARI) for(n=1, 10^6, d=digits(n); p=prod(i=1, #d, d[i]); if(p&&!(p^2%n), print1(n, ", "))) \\ Derek Orr, Apr 29 2015
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Paolo P. Lava and Giorgio Balzarotti, May 08 2007
STATUS
approved