OFFSET
1,1
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
EXAMPLE
a(1) = gcd(2,4) = 2;
a(2) = gcd(2+3,4+6) = gcd(5,10) = 5;
a(3) = gcd(2+3+5,4+6+8) = gcd(10,18) = 2;
a(4) = gcd(2+3+5+7,4+6+8+9) = gcd(17,19) = 1.
MATHEMATICA
Module[{nn=90, pr, cmp}, pr=Accumulate[Prime[Range[nn]]]; cmp=Accumulate[ Take[Select[Range[2nn], CompositeQ], nn]]; GCD@@#&/@Thread[{pr, cmp}]] (* Harvey P. Dale, Jul 29 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 03 2011
STATUS
approved