OFFSET
0,2
LINKS
Antti Karttunen, Table of n, a(n) for n = 0..5040 (corrected by Ray Chandler, Jan 19 2019)
Tyler Ball, Joanne Beckford, Paul Dalenberg, Tom Edgar, and Tina Rajabi, Some Combinatorics of Factorial Base Representations, J. Int. Seq., Vol. 23 (2020), Article 20.3.3.
EXAMPLE
5 has factorial base representation A007623(5) = "21" (as 2*2 + 1*1 = 5). Adding one to these digits and multiplying, we get 3*2 = 6, thus a(5)=6.
MATHEMATICA
a[n_] := Module[{k = n, m = 2, r, p = 1}, While[{k, r} = QuotientRemainder[k, m]; k != 0|| r != 0, p *= (r+1); m++]; p]; Array[a, 100, 0] (* Amiram Eldar, Feb 13 2024 *)
PROG
(MIT/GNU Scheme):
(define (A227154 n) (apply * (map 1+ (n->factbase n))))
(define (n->factbase n) (let loop ((n n) (fex (if (zero? n) (list 0) (list))) (i 2)) (cond ((zero? n) fex) (else (loop (floor->exact (/ n i)) (cons (modulo n i) fex) (1+ i))))))
(PARI) a(n)=my(b=2, t=1); while(n, t *= n%b + 1; n \= b; b++); t \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Jul 04 2013
EXTENSIONS
a(0)=1 added by Tom Edgar, Jun 05 2017
STATUS
approved