This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A117102 Least n such that nextprime(p*n)>p*nextprime(n) where p traversing prime numbers (if p is prime then nextprime(p)=p). 0
 4, 16, 18, 42, 126, 126, 136, 70, 58, 292, 822, 1872, 1446, 1008, 3318, 2026, 2280, 2842, 7726, 17922, 2136, 5022, 20142, 17550, 19540, 68898, 59082, 18792, 90006, 136540, 246888, 392382, 197088, 144060, 819898, 137956, 1555162, 291198, 909772 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS A(n)+1 is always prime ? A(n) is always even ? LINKS EXAMPLE for p=2 least n such than f(2*n)>2*f(n) and n is composite is 4=a(1) for p=3 least n such than f(3*n)>3*f(n) and n is composite is 16=a(2) PROG (PARI) f(n)=nextprime(n); g(n, a)=for(i=1, a, if(f(n*i)>f(n)*f(i) && !isprime(i), return(i))); forprime (i=1, 150, print1(g(i, 5000000), ", ")) CROSSREFS Sequence in context: A224705 A243298 A139719 * A077476 A282552 A278315 Adjacent sequences:  A117099 A117100 A117101 * A117103 A117104 A117105 KEYWORD easy,nonn AUTHOR Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), Apr 18 2006 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 May 27 06:24 EDT 2019. Contains 323599 sequences. (Running on oeis4.)