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A057467
GCD of n-th and (n+1)-st term in the sequence of first differences between primes, A001223.
6
1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 6, 2, 2, 2, 2, 2, 2, 2, 2, 4, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 6, 2, 2, 6, 2, 2, 2, 2, 2, 2, 12, 4, 2, 2, 2, 2, 2, 2, 6, 6, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 6, 2, 2, 2, 4, 4, 2, 2, 2, 2, 2, 2, 2, 2, 4, 2, 2, 4, 4, 4, 4, 4, 2, 6, 2, 2, 6, 2, 2, 6, 2, 2
OFFSET
1,2
FORMULA
a(n) = gcd( A001223(n+1), A001223(n) ).
MATHEMATICA
Map[GCD @@ # &, Partition[#, 2, 1] &@ Differences@ Prime@ Range@ 100] (* Michael De Vlieger, Feb 18 2017 *)
CROSSREFS
Cf. A001223.
Sequence in context: A135663 A090620 A151659 * A074594 A211667 A001069
KEYWORD
nonn,easy
AUTHOR
Labos Elemer, Dec 06 2000
STATUS
approved