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 A173269 2*prime(prime(n))-3 and 3*prime(prime(n))-2 are both primes. 1

%I

%S 1,2,3,8,11,14,15,19,23,24,28,39,44,47,54,62,63,81,85,101,121,122,124,

%T 136,152,159,180,218,219,241,247,253,274,290,298,307,323,324,341,361,

%U 371,376,381,403,410,413,441,443,479,487,499,552,554,556,562,582,622

%N 2*prime(prime(n))-3 and 3*prime(prime(n))-2 are both primes.

%e a(1)=1 because 2*p(p(1))-3=2*p(2)-3=2*3-3=3=prime and 3*p(p(1))-2=7=prime; a(2)=2 because 2*p(p(2))-3=2*p(3)-3=2*5-3=7=prime and 3*p(p(2))-2=13=prime; a(3)=3 because 2*p(p(3))-3=2*p(5)-3=2*11-3=19=prime and 3*p(p(3))-2=31=prime; a(4)=8 because 2*p(p(8))-3=2*p(19)-3=2*67-3=131=prime and 3*p(p(8))-2=199=prime.

%Y Cf. A063908, A088878.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Feb 14 2010

%E Inserted 23 and 24, removed 34, extended the sequence - _R. J. Mathar_, Mar 01 2010

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Last modified January 29 23:01 EST 2023. Contains 359939 sequences. (Running on oeis4.)