A126937 A dragon curve is drawn on an Ulam spiral; a(n) is the integer written in the cell reached at step n.

0, 1, 8, 7, 22, 21, 6, 19, 20, 41, 40, 19, 18, 39, 38, 67, 68, 105, 104, 67, 66, 37, 38, 17, 16, 37, 36, 35, 62, 63, 98, 99, 64, 101, 100, 99, 142, 141, 98, 97, 140, 139, 96, 97, 62, 61, 34, 33, 60, 61, 96, 95, 138, 137, 94, 93, 136, 137, 188, 187, 246, 247, 314, 315, 248

Offset: 0

Author

Philippe Lallouet (philip.lallouet(AT)wanadoo.fr), Mar 18 2007

Keywords

• nonn

Comments

The spiral consists of the numbers 0, 1, 2, ... written in a spiral on squared paper. The dragon curve is a self-similar curve starting at the same point. See the illustration for more information.

Links

• Philippe Lallouet, Spreadsheet with illustration of initial terms
• Eric Weisstein's World of Mathematics, Dragon Curve [From _Klaus Brockhaus_, Aug 07 2008]
• Eric Weisstein's World of Mathematics, Prime Spiral [From _Klaus Brockhaus_, Aug 07 2008]

Crossrefs

Cf. A014577 (regular paper-folding [or dragon curve] sequence). [From Klaus Brockhaus, Aug 07 2008]

Extensions

Edited by N. J. A. Sloane, Mar 28 2007

a(9) - a(64) from Klaus Brockhaus, Aug 07 2008