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A105361
Rearrangement of positive integers according to decimal expansions of Pi and e (see comments).
2
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.
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
KEYWORD
nonn,base
AUTHOR
Zak Seidov, Apr 01 2005
EXTENSIONS
Edited by Robert G. Wilson v, Apr 02 2005
STATUS
approved