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.

A162015 Numbers n with property that the sum of the digits of n is substring of n and of n^2.

Original entry on oeis.org

1, 5, 6, 10, 50, 60, 100, 500, 600, 910, 1000, 1009, 1018, 1027, 1036, 1045, 1054, 1090, 1128, 1145, 1309, 1454, 1463, 1654, 1781, 1810, 2127, 2499, 2710, 3610, 3613, 4105, 4175, 4510, 5000, 5410, 6000, 6123, 6133, 6310, 7152, 7210, 7212, 8110, 8131, 9010
Offset: 1

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Author

Claudio Meller, Jun 24 2009

Keywords

Comments

1454 is in the list because its digital sum is 1+4+5+4 = 14 and "14" is a substring of 1454 and of 1454^2 = 2114116

Crossrefs

Programs

  • Mathematica
    sdssQ[n_]:=Module[{idn1=IntegerDigits[n],idn2=IntegerDigits[n^2],idnt}, idnt= IntegerDigits[ Total[idn1]];SequenceCount[idn1,idnt]>0 && SequenceCount[idn2,idnt]>0]; Select[Range[10000],sdssQ] (* The program uses the SequenceCount function from Mathematica version 10 *) (* Harvey P. Dale, Jul 29 2015 *)