OFFSET
1,2
LINKS
Hugo Pfoertner, Table of n, a(n) for n = 1..52.
MATHEMATICA
1/2*Union@ FoldList[Max, Array[Times @@ FactorInteger[Times @@ Range[#1 + 1, #2 - 1]][[All, 1]] & @@ Map[Prime, # + {0, 1}] &, 180, 2]] (* Michael De Vlieger, May 20 2022 *)
PROG
(Python)
from sympy import sieve as p, primefactors
def A076978_halfen(n): # for all integers n > 1
result = 1
for composites in range(p[n]+1, p[n+1]):
for primefactor in primefactors(composites):
if result % primefactor != 0: result *= primefactor
return result//2
A354218 = [1]
for n in range(2, 180):
print(A354218) # Karl-Heinz Hofmann, May 20 2022
(PARI) a354218(maxterm) = {my(mp=0, pp=3); forprime(p=5, oo, my(L=List()); for(j=pp+1, p-1, my(f=factor(j), nf=#f~); for(k=1, nf, listput(~L, f~[1, k]))); listsort(L, 1); my(mpp=prod(k=1, #L, L[k])); if(mpp>mp, if(mpp<2*maxterm, print1(mpp/2, ", "); mp=mpp, return)); pp=p)};
a354218(10^75)
CROSSREFS
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, May 19 2022
STATUS
approved