A181672 The odd terms (a1,a3,a5,...) are in an arithmetic progression (1,2,3,...), while the even terms (a2,a4,a6,...) give the number of letters of the given odd term.

1, 3, 2, 3, 3, 5, 4, 4, 5, 4, 6, 3, 7, 5, 8, 5, 9, 4, 10, 3, 11, 6, 12, 6, 13, 8, 14, 8, 15, 7, 16, 7, 17, 9, 18, 8, 19, 8, 20, 6, 21, 9, 22, 9, 23, 11, 24, 10, 25, 10, 26, 9, 27, 11, 28, 11, 29, 10, 30, 6, 31, 9, 32, 9, 33, 11, 34, 10

Offset: 1

Author

Edwin F. Sampang, Nov 04 2010

Keywords

• nonn
• word
• easy

Examples

			(ONE - 3 letters, TWO - 3 letters, THREE - 5 letters, FOUR - 4 letters, FIVE - 4 letters...)
		

Formula

a(2n-1) = n.

a(2n) = A005589(n).

Extensions

More terms from Nathaniel Johnston, Nov 15 2010