OFFSET
0,2
COMMENTS
LINKS
EXAMPLE
MATHEMATICA
f[n_] := Product[Prime[k], {k, 1, n}]; Table[Times @@ (f[Length[#]]&) /@ Select[Split[IntegerDigits[n, 2]], #[[1]] == 1&], {n, 0, 94}] (* Jean-François Alcover, Jul 11 2017 *)
PROG
(Scheme)
(define (A278159 n) (fold-left (lambda (a r) (* a (A002110 r))) 1 (bisect (reverse (binexp->runcount1list n)) (- 1 (modulo n 2)))))
;; See A227349 for the required other functions.
(Python)
from math import prod
from re import split
from sympy import primorial
def RLT(n, f):
""" run length transform of a function f """
return prod(f(len(d)) for d in split('0+', bin(n)[2:]) if d != '') if n > 0 else 1
def A278159(n): return RLT(n, primorial) # Chai Wah Wu, Feb 04 2022
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Nov 16 2016
STATUS
approved