A117391 - OEIS

A117391

a(n) = Max{gcd(i,j): prime(n) < i < prime(n+1) < j < prime(n+2)}.

2, 3, 4, 4, 3, 3, 7, 6, 6, 8, 3, 3, 5, 8, 6, 6, 7, 4, 6, 5, 8, 12, 10, 3, 3, 4, 4, 14, 13, 8, 6, 6, 10, 6, 9, 5, 5, 8, 6, 10, 8, 4, 3, 11, 20, 9, 4, 4, 7, 6, 10, 11, 9, 7, 6, 6, 8, 3, 6, 19, 14, 4, 4, 15, 16, 9, 6, 4, 7, 7, 12, 9, 5, 5, 12, 10, 8, 13, 10, 10, 9, 6, 7, 8, 12, 10, 3, 3, 8, 18, 10, 8, 5, 5

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OFFSET

2,1

LINKS

Table of n, a(n) for n=2..95.

FORMULA

a(A049084(A117392(n)) - 1) = n.

EXAMPLE

a(20) = Max{gcd(i,j): prime(20) < i < prime(21) < j < prime(22)} =

Max{gcd(i,j): 71 < i < 73 < j < 79} =

Max{gcd(72,74), gcd(72,75), gcd(72,76), gcd(72,77), gcd(72,78)} =

Max{2, 3, 4, 1, 6} = 6.