This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A107819 Slowest increasing sequence where a(n)+n is prime. 1
 1, 3, 4, 7, 8, 11, 12, 15, 20, 21, 26, 29, 30, 33, 38, 43, 44, 49, 52, 53, 58, 61, 66, 73, 76, 77, 80, 81, 84, 97, 100, 105, 106, 115, 116, 121, 126, 129, 134, 139, 140, 149, 150, 153, 154, 165, 176, 179, 180, 183 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Appears to be closely related to A014692. LINKS EXAMPLE (1)+1=2, which is prime; (3)+2=5=prime; (4)+3=7=prime; (7)+4=11=prime; (8)+5=13=prime; etc. MAPLE A107819 := proc(n)         option remember;         if n = 1 then                 return 1;         else                 for a from procname(n-1)+1 do                         if isprime(a+n) then                                 return a;                         end if;                 end do:         end if; end proc: # R. J. Mathar, Sep 05 2011 PROG (Sage) @cached_function def A107819(n): ....prev = (-1 if n == 1 else A107819(n-1)) ....return next_prime(prev+n)-n  # D. S. McNeil, Sep 05 2011 CROSSREFS Sequence in context: A309388 A188259 A058235 * A300950 A067186 A133675 Adjacent sequences:  A107816 A107817 A107818 * A107820 A107821 A107822 KEYWORD easy,nonn AUTHOR Eric Angelini, Jun 11 2005 EXTENSIONS Corrected by R. J. Mathar, Sep 05 2011 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 October 14 02:19 EDT 2019. Contains 327994 sequences. (Running on oeis4.)