A227290 Repeatedly map numbers to number of letters in English name (A005589); sequence gives first number that needs n steps to get to 4.

4, 0, 3, 1, 11, 23, 323, 1103323373373373373373373373373

Offset: 0

Author

Roland Kneer, Jul 05 2013

Keywords

• nonn
• word

Comments

Based on the observation by Diane Karloff that the trajectory of A005589 always converges to 4.

40311123323 (concatenation of the first seven terms) is the first time prime is obtained when concatenating k first initial terms of the sequence. - Jonathan Vos Post, Jul 06 2013, edited by Antti Karttunen, Jul 25 2013

Examples

			"eleven" has 6 letters, "six" has 3 letters, "three" has 5 letters, "five" has 4 letters.
So a(4)=11, as A005589^4(11)=4 and 11 is the first such number.
But a(3)=1, because "one" is the same length as "six".
		

Crossrefs

Cf. A016037.