This site is supported by donations to The OEIS Foundation.

 Annual Appeal: Please make a donation to keep the OEIS running. In 2018 we replaced the server with a faster one, added 20000 new sequences, and reached 7000 citations (often saying "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A066197 Squarefree kernel of (n*prime(n))*(n+prime(n)). 1
 6, 30, 30, 154, 110, 1482, 714, 114, 138, 11310, 14322, 1554, 3198, 34314, 43710, 7314, 38114, 28914, 109478, 64610, 144102, 175538, 202354, 60342, 59170, 333502, 40170, 22470, 436218, 484770, 622046, 42706, 768570, 817598, 239890, 169422 (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 Ivars Peterson, The Amazing ABC Conjecture M. Waldschmidt, Open Diophantine problems Eric Weisstein's World of Mathematics, ABC Conjecture Eric Weisstein's World of Mathematics, Squarefree Wikipedia, abc conjecture FORMULA a(n) = A007947(A033286(n) * A014688(n)). EXAMPLE For n=20 we have: A = n = 20, B = A000040(20) = 71, C = A + B = 20 + 71 = 91 and A*B*C = 129220 with squarefree kernel a(20) = 64610 = 2*5*7*13*71. PROG (PARI) a(n)=my(p=prime(n), f=vecsort(concat(concat(p, factor(n)[, 1]), factor(n+p)[, 1]), , 8)~); prod(i=1, #f, f[i]) \\ Charles R Greathouse IV, Jul 23 2013 (Haskell) a066197 n = a007947 \$ a033286 n * a014688 n -- Reinhard Zumkeller, Jul 24 2013 CROSSREFS Sequence in context: A260017 A123624 A287733 * A078638 A068510 A147798 Adjacent sequences:  A066194 A066195 A066196 * A066198 A066199 A066200 KEYWORD nonn AUTHOR Reinhard Zumkeller, Dec 15 2001 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 December 13 18:19 EST 2018. Contains 318086 sequences. (Running on oeis4.)