A105361 Rearrangement of positive integers according to decimal expansions of Pi and e (see comments).

2, 1, 4, 3, 6, 8, 10, 5, 12, 7, 14, 16, 9, 18, 20, 11, 13, 15, 22, 24, 17, 26, 28, 19, 21, 23, 30, 32, 25, 34, 36, 27, 29, 31, 38, 33, 35, 37, 40, 39, 41, 42, 44, 46, 43, 48, 45, 47, 49, 51, 53, 55, 50, 57, 59, 61, 52, 63, 65, 67, 69, 71, 54, 73, 75, 77, 56, 58, 79, 81, 83, 85

Offset

1,1

Comments

Take decimal expansions of Pi and e:

p = 3,1,4,1,5,9,2,6,5,3,5,8,9,...(A000796) and

e = 2,7,1,8,2,8,1,8,2,8,4,5,9,...(A001113).

If p(n) > e(n), then a(n) is the next even number; otherwise, a(n) is the next odd number.

Links

Table of n, a(n) for n=1..72.

Index entries for sequences that are permutations of the natural numbers

Mathematica

p = RealDigits[Pi, 10, 100][[1]]; e = RealDigits[E, 10, 100][[1]]; r = Range[100]; a[n_] := a[n] = Block[{c = Complement[r, Table[ a[i], {i, n - 1}]]}, If[p[[n]] > e[[n]], Select[c, EvenQ[ # ] &][[1]], Select[c, OddQ[ # ] &][[1]]]]; Table[ a[n], {n, 72}] (* Robert G. Wilson v, Apr 02 2005 *)

Crossrefs

Cf. A105362.

Sequence in context: A114862 A064579 A277376 * A370728 A125154 A281853

Adjacent sequences: A105358 A105359 A105360 * A105362 A105363 A105364

Keyword

nonn,base

Author

Zak Seidov, Apr 01 2005

Extensions

Edited by Robert G. Wilson v, Apr 02 2005

Status

approved