The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A174055 Sums of three Mersenne primes. 4
 9, 13, 17, 21, 37, 41, 45, 65, 69, 93, 133, 137, 141, 161, 165, 189, 257, 261, 285, 381, 8197, 8201, 8205, 8225, 8229, 8253, 8321, 8325, 8349, 8445, 16385, 16389, 16413, 16509, 24573, 131077, 131081, 131085, 131105, 131109, 131133, 131201, 131205, 131229, 131325, 139265, 139269, 139293, 139389, 147453, 262145, 262149 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..969 FORMULA A000668(i) + A000668(j) + A000668(k), with integers i,j,k not necessarily distinct. The subsequence of prime sums of three Mersenne primes is A174056. 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 Cf. A000668, A155877, A166484, A171251, A171252, A171253, A171254, A171255, A174056, A174057. Sequence in context: A329388 A227062 A134441 * A273059 A188220 A211429 Adjacent sequences:  A174052 A174053 A174054 * A174056 A174057 A174058 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 27 11:29 EDT 2021. Contains 347689 sequences. (Running on oeis4.)