This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A291206 Semi-octavan primes: primes of the form x^4 + y^8. 2
 2, 17, 257, 337, 881, 1297, 2657, 6577, 10657, 14897, 16561, 28817, 65537, 65617, 66161, 80177, 83777, 149057, 160001, 166561, 260017, 280097, 331777, 391921, 394721, 411361, 463537, 596977, 614657, 621217, 847601 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 A. J. C. Cunningham, High quartan factorisations and primes, Messenger of Mathematics 36 (1907), pp. 145-174. EXAMPLE a(1) = 1^4 + 1^8 = 2. a(2) = 2^4 + 1^8 = 17. a(3) = 1^4 + 2^8 = 257. a(4) = 3^4 + 2^8 = 337. PROG (PARI) list(lim)=my(v=List([2]), x4, t); for(x=1, sqrtnint(lim\=1, 4), x4=x^4; forstep(y=x%2+1, sqrtnint(lim-x4, 8), 2, if(isprime(t=x4+y^8), listput(v, t)))); Set(v) CROSSREFS Subsequence of A002645. A006686 is a subsequence. Cf. A028916. Sequence in context: A253549 A002590 A029735 * A037896 A099714 A301584 Adjacent sequences:  A291203 A291204 A291205 * A291207 A291208 A291209 KEYWORD nonn AUTHOR Charles R Greathouse IV, Aug 21 2017 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 20 07:17 EDT 2018. Contains 316378 sequences. (Running on oeis4.)