OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..969
FORMULA
EXAMPLE
a(1) = 3 + 3 + 3 = 9. a(2) = 3 + 3 + 7 = 13. a(3) = 3 + 7 + 7 = 17. a(4) = 7 + 7 + 7 = 21. a(5) = 3 + 3 + 31 = 37. a(6) = 3 + 7 + 31 = 41.
MAPLE
N:= 10^6: # to get all terms <= N
for n from 1 while numtheory:-mersenne([n]) < N do od:
S:= {seq(numtheory:-mersenne([i]), i=1..n-1)}:
sort(convert(select(`<=`, {seq(seq(seq(s+t+u, s=S), t=S), u=S)}, N), list)); # Robert Israel, Mar 02 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Mar 06 2010
EXTENSIONS
More terms from Max Alekseyev, Oct 15 2012
Edited by Robert Israel, Mar 02 2016
STATUS
approved