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A358179
Prime numbers with prime indices in A333244.
0
31, 709, 1787, 8527, 19577, 27457, 42043, 52711, 72727, 96797, 112129, 137077, 167449, 173867, 239489, 250751, 285191, 352007, 401519, 443419, 464939, 490643, 527623, 683873, 718807, 755387, 839483, 864013, 985151, 1021271, 1080923, 1128889, 1159901, 1278779, 1323503, 1342907, 1656649, 1693031
OFFSET
1,1
COMMENTS
This sequence can also be generated by the N-sieve.
LINKS
Michael P. May, Properties of Higher-Order Prime Number Sequences, Missouri J. Math. Sci. (2020) Vol. 32, No. 2, 158-170; and arXiv version, arXiv:2108.04662 [math.NT], 2021.
FORMULA
a(n) = prime(A333244(n)).
a(n) = A049090(A333242(n)).
a(n) = A038580(A262275(n)).
a(n) = A006450(A333243(n)).
EXAMPLE
a(1) = prime(A333244(1)) = prime(11) = 31.
MATHEMATICA
b[n_] := b[n] = If[PrimeQ[n], 1+b[PrimePi[n]], 0];
a[n_] := a[n] = Module[{p}, p = If[n==1, 1, a[n-1]]; While[True, p = NextPrime[p]; If[#>3 && OddQ[#]&[b[p]], Break[]]]; p];
Array[a, 50]
PROG
(PARI) b(n)={my(k=0); while(isprime(n), k++; n=primepi(n)); k};
apply(x->prime(prime(prime(prime(x)))), select(n->b(n)%2, [1..500])) \\ Michel Marcus, Nov 18 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Michael P. May, Nov 11 2022
STATUS
approved