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 A351649 a(n) = minimal average of a pair of twin primes m, such that m * twin_prime(n) is the average of another pair of twin primes, or -1 if no m exists. 0

%I #11 Feb 18 2022 21:00:05

%S 4,6,6,18,150,6,12,12,42,30,30,18,462,18,570,42,6,6,102,6,12,12,420,

%T 192,18,600,5100,570,18,4050,30,42,18,60,12,12,6,102,6,6,108,42,42,18,

%U 570,30,180,108,2970,12,60,270,12,60,42,60,1950,102,108,18,72,348

%N a(n) = minimal average of a pair of twin primes m, such that m * twin_prime(n) is the average of another pair of twin primes, or -1 if no m exists.

%H Carlos Rivera, <a href="https://www.primepuzzles.net/puzzles/puzz_1075.htm">Puzzle 1075: A conjecture about twin primes</a>, The Prime Puzzles and Problems Connection.

%e 11 is the fourth twin prime, i.e., A001097(4). 18 is the minimal average of a twin prime pair, i.e., (17,19), where 18*11=198 is the average of the twin prime pair (197,199). So, a(4)=18.

%Y Cf. A001097, A014574.

%K nonn

%O 1,1

%A _Ivan N. Ianakiev_, Feb 16 2022

%E More terms from _Jinyuan Wang_, Feb 16 2022

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