OFFSET
1,1
COMMENTS
EXAMPLE
The sequence of terms together with their prime indices begins:
2: {1}
4: {1,1}
6: {1,2}
7: {4}
8: {1,1,1}
10: {1,3}
11: {5}
12: {1,1,2}
13: {6}
14: {1,4}
16: {1,1,1,1}
18: {1,2,2}
20: {1,1,3}
21: {2,4}
22: {1,5}
23: {9}
24: {1,1,1,2}
MAPLE
with(numtheory):
q:= n-> is(irem(pi(min(factorset(n))), 5) in {0, 1, 4}):
select(q, [$2..100])[]; # Alois P. Heinz, Mar 07 2019
MATHEMATICA
Select[Range[100], Intersection[Mod[If[#==1, {}, PrimePi/@First/@FactorInteger[#]], 5], {0, 1, 4}]!={}&]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 06 2019
STATUS
approved