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 1-2 of 2 results.

A099648 Largest term arising in complete-iteration-list (both transient and cycle) when f(x) = A003132(x) is iterated, i.e., if digit-squares of iterate added repeatedly until steady state (= either cycle or fixed point) is reached.

Original entry on oeis.org

1, 145, 145, 145, 145, 145, 130, 145, 145, 10, 145, 145, 13, 145, 145, 145, 145, 145, 100, 145, 145, 145, 23, 145, 145, 145, 145, 100, 145, 145, 31, 32, 145, 145, 145, 145, 145, 145, 145, 145, 145, 145, 145, 44, 145, 145, 145, 145, 130, 145, 145, 145, 145, 145
Offset: 1

Views

Author

Labos Elemer, Nov 12 2004

Keywords

Examples

			n=2: list = {2,4,16,37,58,89,145,42,20,4,16,37,58,...}; a(2) = max(list) = 145;
For n < 145, max > initial value except few cases. See A099649.
		

Crossrefs

Programs

  • Mathematica
    ed[x_] :=IntegerDigits[x]; func[x_] :=Apply[Plus, ed[x]^2]; itef[x_, ho_] :=NestList[id2, x, 100]; Table[Max[Union[itef[w, 100]]], {w, 1, 256}]

A099652 Largest number arising if f[x]=1+A003132(x) function is iterated until steady state reached. Compare with A099648.

Original entry on oeis.org

107, 107, 107, 107, 107, 107, 107, 107, 118, 107, 107, 107, 107, 107, 107, 107, 107, 107, 107, 107, 107, 118, 107, 107, 107, 107, 107, 118, 107, 107, 107, 107, 107, 107, 35, 53, 107, 107, 107, 107, 107, 107, 107, 107, 107, 53, 107, 107, 146, 107, 107, 107, 53
Offset: 1

Views

Author

Labos Elemer, Nov 12 2004

Keywords

Examples

			n=32: list={32,14,18,66,73,59,107,51,27,54,42,21,6,37,59,107,51,...},
max[list]=a[32]=107>initial-value;
Also:lengths of transient=5,of cycle=0 (see in A099646).
		

Crossrefs

Programs

  • Mathematica
    ed[x_] :=IntegerDigits[x];func[x_] :=Apply[Plus, ed[x]^2]+1; Table[Max[NestList[func, w, 200]], {w, 1, 150}]
Showing 1-2 of 2 results.