cp's OEIS Frontend

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.

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.

Original entry on oeis.org

0, 13, 113, 2410, 4113, 6113, 8210, 14113, 23410, 28113, 33113, 34010, 35113, 51113, 62113, 71113, 76610, 81410, 93113, 101310, 117010, 123113, 242210, 253113, 279710, 298113, 300113, 351010, 513410, 529113, 544113, 616113, 634113
Offset: 1

Views

Author

Patrick De Geest, Mar 15 1999

Keywords

Examples

			28113 = (2)(8)(1)(1)(3) -> (3)(19)(2)(2)(5) = 319225 = 565^2.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[0,650000],IntegerQ[Sqrt[FromDigits[Flatten[IntegerDigits/@ (If[#==0,1,Prime[#]]&/@IntegerDigits[#])]]]]&]  (* Harvey P. Dale, Mar 27 2011 *)

Extensions

Definition edited and offset corrected by M. F. Hasler, Oct 11 2019