OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
The powerful numbers (A001694) start 1, 4, 8, 9, ... Now 11 = 1+1+9 and is not the sum of fewer terms, so 11 is in the sequence.
MATHEMATICA
With[{m = 200}, pow = Select[Range[m], # == 1 || Min[FactorInteger[#][[;; , 2]]] > 1 &]; s2 = Select[Union[Plus @@@ Tuples[pow, {2}]], # <= m &]; s3 = Select[Union[Plus @@@ Tuples[pow, {3}]], # <= m &]]; Complement[s3, pow, s2] (* Amiram Eldar, Feb 12 2023 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jud McCranie, Jul 13 2001
EXTENSIONS
Offset corrected by Amiram Eldar, Feb 12 2023
STATUS
approved