Jelly, (削除) 15 (削除ここまで) 14 bytes
’ÆRμ_2fμ+2;μİS
How it works
’ÆRμ_2fμ+2;μİS Main link. Argument: n
’ Decrement; yield n-1.
ÆR Prime range; yield all primes in [1, ..., n-1].
μ New chain. Argument: r (prime range)
_2 Subtract 2 from all primes.
f Filter; keep all p-2 that appear in r.
μ New chain. Argument: t (filtered range)
+2 Add 2 to all primes in s.
; Concatenate with s.
μ New chain. Argument: t (twin primes)
İ Take the inverses.
S Sum.
Jelly, (削除) 15 (削除ここまで) 14 bytes
’ÆRμ_2fμ+2;μİS
How it works
’ÆRμ_2fμ+2;μİS Main link. Argument: n
’ Decrement; yield n-1.
ÆR Prime range; yield all primes in [1, ..., n-1].
μ New chain. Argument: r (prime range)
_2 Subtract 2 from all primes.
f Filter; keep all p-2 that appear in r.
μ New chain. Argument: t (filtered range)
+2 Add 2 to all primes in s.
; Concatenate with s.
μ New chain. Argument: t (twin primes)
İ Take the inverses.
S Sum.