A122241 Iterates of A122237, starting from 4.

4, 22, 54, 169, 516, 1841, 6076, 19256, 66140, 252691, 888179, 2900616

Offset: 1

Author

Antti Karttunen, Sep 14 2006

Keywords

• nonn

Comments

It might be more natural to use offset 0 for the initial value a(0) = 4 since that's not the result of an actual iteration of the map A122237. However, some other sequences (A122242, A179845, A179841, ...?) depend on this and have b-files that would require to be changed. - M. F. Hasler, Jul 18 2025

Crossrefs

Cf. A122237 = A057548 o A082358, A122242 = A014486 o A122241.

Programs

Scheme

(define (A122241 n) (if (= 1 n) 4 (A122237 (A122241 (- n 1)))))

Formula

a(n+1) = A122237(a(n)) for n >= 1; a(1) = 4.