This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A048383 #20 Oct 13 2019 23:25:59 %S A048383 0,13,113,2410,4113,6113,8210,14113,23410,28113,33113,34010,35113, %T A048383 51113,62113,71113,76610,81410,93113,101310,117010,123113,242210, %U A048383 253113,279710,298113,300113,351010,513410,529113,544113,616113,634113 %N A048383 Numbers k such that replacing each nonzero digit d with the d-th prime (replacing each 0 digit with a 1) yields a square. %e A048383 28113 = (2)(8)(1)(1)(3) -> (3)(19)(2)(2)(5) = 319225 = 565^2. %t A048383 Select[Range[0,650000],IntegerQ[Sqrt[FromDigits[Flatten[IntegerDigits/@ (If[#==0,1,Prime[#]]&/@IntegerDigits[#])]]]]&] (* _Harvey P. Dale_, Mar 27 2011 *) %Y A048383 Cf. A000290, A048380, A048384. %K A048383 nonn,base %O A048383 1,2 %A A048383 _Patrick De Geest_, Mar 15 1999 %E A048383 Definition edited and offset corrected by _M. F. Hasler_, Oct 11 2019