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.

Showing 1-3 of 3 results.

A214880 5-adic valuation of A007185.

Original entry on oeis.org

1, 2, 4, 4, 5, 6, 7, 8, 9, 10, 11, 12, 17, 14, 15, 18, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 29, 29, 30, 33, 33, 33, 35, 35, 36, 37, 38, 40, 40, 41, 42, 43, 44, 45, 46, 47, 48, 50, 51, 54, 54, 54, 54, 55, 56, 57, 58, 59, 61, 61, 63, 63, 66, 66, 66, 67
Offset: 1

Views

Author

Eric M. Schmidt, Jul 29 2012

Keywords

Comments

a(n) >= n.
It appears that the density of n such that a(n) = n is 4/5.

Links

Crossrefs

Cf. A214881, A214882, A214883.

Programs

  • GAP
    A214880 := function(max) local result, i; result := [5]; for i in [2..max] do Add(result, result[i-1]^2 mod 10^i); od; result := List(result, x->Valuation(x, 5)); return result; end;

A214881 2-adic valuation of A016090.

Original entry on oeis.org

1, 2, 3, 5, 5, 6, 8, 8, 9, 13, 14, 14, 14, 14, 15, 17, 17, 18, 21, 21, 22, 23, 26, 26, 26, 26, 27, 28, 30, 30, 31, 32, 34, 34, 36, 36, 38, 38, 39, 42, 41, 48, 43, 44, 49, 46, 47, 49, 52, 51, 51, 52, 53, 56, 56, 56, 63, 58, 59, 60, 61, 65, 64, 64, 66, 66, 67
Offset: 1

Views

Author

Eric M. Schmidt, Jul 29 2012

Keywords

Comments

a(n) >= n.
It appears that the density of n such that a(n) = n is 1/2.

Links

Crossrefs

Cf. A016090, A214880, A214882, A214883.

Programs

  • GAP
    A214881 := function(max) local result, i; result := [6]; for i in [2..max] do Add(result, (2*result[i-1] - result[i-1]^2) mod 10^i); od; result := List(result, x->Valuation(x, 2)); return result; end;

A214882 A007185(n)/5^n.

Original entry on oeis.org

1, 1, 5, 1, 29, 57, 37, 33, 109, 841, 373, 3761, 8125, 9817, 8517, 41025, 73741, 67177, 118293, 967377, 822621, 3100537, 6492133, 16397921, 33478573, 13406601, 83211957, 177703665, 35540733, 114482329, 881889925, 176377985, 35275597, 15468937385, 3093787477
Offset: 1

Views

Author

Eric M. Schmidt, Jul 31 2012

Keywords

Comments

Conjecture: For any odd m and for any k, the density of n such that a(n) == k (mod m) is 1/m.

Links

Crossrefs

Cf. A214880, A214881, A214883.

Programs

  • GAP
    A214882 := function(max) local result, i; result := [5]; for i in [2..max] do Add(result, result[i-1]^2 mod 10^i); od; result := List([1..max], n->result[n]/5^n); return result; end;
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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