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.

A174800 Number whose product of digits is a square.

Original entry on oeis.org

0, 1, 4, 9, 10, 11, 14, 19, 20, 22, 28, 30, 33, 40, 41, 44, 49, 50, 55, 60, 66, 70, 77, 80, 82, 88, 90, 91, 94, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 114, 119, 120, 122, 128, 130, 133, 140, 141, 144, 149, 150, 155, 160, 166, 170, 177, 180, 182, 188, 190, 191, 194, 199, 200
Offset: 0

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Author

Michel Lagneau, Dec 01 2010

Keywords

Comments

Differs from A062371 in that here the digit 0 is included in the product and so every number containing a zero belongs to this sequence. - D. S. McNeil, Dec 01 2010

Examples

			149 is in the sequence because 1*4*9 = 6^2; 20 is in the sequence because 2*0 = 0^2.
		

Crossrefs

Cf. A062371.

Programs

  • Mathematica
    Select[Range[1000], IntegerQ[Sqrt[Times @@ (IntegerDigits[#])]] &]