A256491 a(n) = prime(prime(n) + n - 2).
2, 5, 13, 23, 43, 59, 79, 97, 113, 157, 173, 211, 239, 257, 281, 331, 373, 389, 433, 461, 479, 523, 569, 607, 659, 691, 719, 751, 769, 811, 911, 947, 997, 1019, 1091, 1103, 1163, 1217, 1249, 1297, 1361, 1381, 1459, 1483, 1511, 1543, 1619, 1723, 1759, 1787, 1831
Offset: 1
Keywords
Examples
a(3) = prime(prime(3) + 3 - 2) = prime(5 + 3 - 2) = prime(6) = 13. a(4) = prime(prime(4) + 4 - 2) = prime(7 + 4 - 2) = prime(9) = 23. a(5) = prime(prime(5) + 4 - 2) = prime(11 + 4 - 2) = prime(13) = 43.
Crossrefs
Cf. A256464.
Programs
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Mathematica
Table[Prime[Prime[n] + n - 2], {n, 51}] (* Jon Maiga, Nov 20 2018 *) -
PARI
a(n) = {i = prime(n); stop = 0; while (! stop, vab = vector(i, k, sigma(k)/k); w = vecsort(vab, , 1); pos = posv(n, w); if (pos == n, stop=1, i++);); i;}
Formula
a(n) = A256464(prime(n)).
Extensions
Name clarified by Alonso del Arte, Nov 20 2018, was "A256464(prime(n))."
Comments