A105353 Rearrangement of positive integers: parity of a(n) coincides with parity of n-th digit of decimal expansion of Pi (see comments).

1, 3, 2, 5, 7, 4, 9, 11, 13, 6, 8, 15, 17, 19, 10, 21, 23, 25, 27, 12, 29, 14, 16, 18, 20, 22, 24, 31, 33, 26, 35, 28, 37, 39, 41, 30, 32, 34, 36, 38, 43, 45, 47, 49, 40, 51, 53, 55, 57, 59, 61, 63, 65, 42, 67, 44, 46, 48, 69, 71, 50, 73, 52, 54, 75, 77, 56, 79, 58, 81, 60, 83

Offset

1,2

Comments

Take decimal expansion of pi: 3,1,4,1,5,9,2,6,5,... First digit pi(1)=3, hence a(1)=1; pi(2)=1, hence a(2)=3, pi(3)=4, hence a(3)=2, etc.

Links

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

Crossrefs

Cf. A105354 - A105360.

Sequence in context: A006369 A097284 A276684 * A115966 A338744 A338745

Adjacent sequences: A105350 A105351 A105352 * A105354 A105355 A105356

Keyword

nonn,base

Author

Zak Seidov, Apr 01 2005

Status

approved