OFFSET
1,1
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..10000
MATHEMATICA
Table[Times @@ MapIndexed[Prime[First[#2]]^#1 &, Sort[FactorInteger[n + DivisorSigma[0, n]][[All, -1]], Greater]], {n, 106}] (* Michael De Vlieger, May 21 2017 *)
PROG
(PARI)
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ This function from Charles R Greathouse IV, Aug 17 2011
for(n=1, 10000, write("b286479.txt", n, " ", A286479(n)));
(Python)
from sympy import factorint, divisor_count
def P(n):
f = factorint(n)
return sorted([f[i] for i in f])
def a046523(n):
x=1
while True:
if P(n) == P(x): return x
else: x+=1
def a(n): return a046523(n + divisor_count(n)) # Indranil Ghosh, May 21 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 21 2017
STATUS
approved