OFFSET
1,1
COMMENTS
Add both primes of the pair as well as their prime indices. Example: prime(11) - prime(10) = 31 - 29 = 2; prime(10) + prime(11) + 10 + 11 = 81 = 9^2 = a(1).
MATHEMATICA
Select[#[[1]]+#[[2]]+PrimePi[#[[1]]]+PrimePi[#[[2]]]&/@Select[ Partition[ Prime[Range[3*10^6]], 2, 1], #[[2]]-#[[1]]==2&], IntegerQ[Sqrt[#]]&] (* Harvey P. Dale, Feb 29 2020 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Zak Seidov, Sep 22 2003
EXTENSIONS
More terms from Ray Chandler, Sep 25 2003
STATUS
approved