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A180100
a(n) = smallest number k such that five consecutive prime numbers prime(n), prime(n+1), prime(n+2), prime(n+3) and prime(n+4) are divisors of k, k+1, k+2, k+3, and k+4 respectively.
2
788, 789, 40830, 142933, 420068, 709800, 4372298, 1229395, 16530376, 21985509, 28051993, 70973992, 185156451, 330508793, 133276396, 273856936, 1164119973, 994656606, 912355750, 640476303, 3366929360, 706420054, 4180201127
OFFSET
1,1
EXAMPLE
a(8) = 1229395 as prime(8) = 19 =>
1229395 = 19*64705 ;
1229396 = 23*53452 ;
1229397 = 29*42393 ;
1229398 = 31*39658 ;
1229399 = 37*33227.
MAPLE
with(numtheory):for p from 1 to 50 do: p1:=ithprime(p):p2:=ithprime(p+1):p3:=ithprime(p+2):p4:=ithprime(p+3):p5:=ithprime(p+4):it:=0:for n from 1 to 5000000 while(it=0) do:if irem(n, p1)=0 and irem(n+1, p2)=0 and irem(n+2, p3)=0 and irem(n+3, p4)=0 and irem(n+4, p5)=0 then it:=1:printf(`%d, `, n):else fi:od:od:
PROG
(Sage) def A180100(n): return crt([-4..0][::-1], [nth_prime(i) for i in [n..n+4]]) # D. S. McNeil, Jan 16 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Jan 16 2011
STATUS
approved