The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A111096 Partial sums of A137701. 2
 16, 232, 59281, 10059281, 4049575228945, 1950244643588320, 30041944445326335483061, 32095019157463691981298869, 142108579247039194637916834814494, 108199957883829576141601541930838816381470, 118558455387984539329682688832638841343258239487 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) is prime for n = 3, 4, ..., a(n) is semiprime for n = 7, 8, 11, ... LINKS Table of n, a(n) for n=1..11. FORMULA a(n) = Sum_{i=1..n} A001358(i)^A000040(i). EXAMPLE a(1) = 16 because semiprime(1)^prime(1) = 4^2 = 16. a(2) = 232 because 4^2 + 6^3 = 232. a(3) = 59281 = 4^2 + 6^3 + 9^5, which is a prime. a(4) = 10059281 = 4^2 + 6^3 + 9^5 + 10^7, which is a prime. a(7) = 4^2 + 6^3 + 9^5 + 10^7 + 14^11 + 15^13 + 21^17 = 428081461 * 70178102025601, which is semiprime. a(8) = 4^2 + 6^3 + 9^5 + 10^7 + 14^11 + 15^13 + 21^17 + 22^19 = 47 * 682872748031142382580827, which is semiprime. a(11) = 4^2 + 6^3 + 9^5 + 10^7 + 14^11 + 15^13 + 21^17 + 22^19 + 25^23 + 26^29 + 33^31 = 17 * 6974026787528502313510746401919931843721072911 which is semiprime. CROSSREFS Cf. A000040, A001358, A137701, A125580. Sequence in context: A222389 A222938 A265469 * A283853 A266099 A264343 Adjacent sequences: A111093 A111094 A111095 * A111097 A111098 A111099 KEYWORD easy,nonn,less AUTHOR Jonathan Vos Post, Oct 13 2005 STATUS approved

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

Last modified September 11 13:05 EDT 2024. Contains 375829 sequences. (Running on oeis4.)