OFFSET
1,1
COMMENTS
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
The sequence of terms together with their prime indices begins:
4: {1,1}
12: {1,1,2}
18: {1,2,2}
20: {1,1,3}
27: {2,2,2}
28: {1,1,4}
44: {1,1,5}
50: {1,3,3}
52: {1,1,6}
60: {1,1,2,3}
68: {1,1,7}
76: {1,1,8}
84: {1,1,2,4}
90: {1,2,2,3}
92: {1,1,9}
98: {1,4,4}
MATHEMATICA
Select[Range[2, 100], With[{f=FactorInteger[#]}, PrimePi[f[[1, 1]]]==Total[Last/@f]-Length[f]]&]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 06 2019
STATUS
approved