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%I #18 Feb 09 2023 04:43:50
%S 3,4,6,10,216
%N Indices of primes in A001003.
%C a(6), if it exists, is > 1.5*10^6. - _Robert Price_, Apr 16 2014
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SuperCatalanNumber.html">Super Catalan Number</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/IntegerSequencePrimes.html">Integer Sequence Primes</a>
%o (PARI) s(m)= { if (m==1, return(a1)); if (m==2, return(a2)); r = (3*(2*m - 3)*a2 - (m - 3)*a1)/m; a1=a2; a2=r; return(r); }
%o { a1=1; a2=1; n=0; for (m=1, 300, a=s(m); if (isprime(a), n++; print1(m, ", "))); } \\ _Harry J. Smith_, Jun 21 2009
%Y Cf. A001003, A092840.
%K nonn,more
%O 1,1
%A _Eric W. Weisstein_, Mar 07 2004
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