A200260 Numbers k such that k-th prime has an odd digit sum.

2, 3, 4, 9, 10, 13, 14, 15, 18, 19, 23, 24, 30, 32, 33, 34, 36, 37, 40, 41, 43, 44, 45, 46, 48, 49, 50, 53, 56, 57, 60, 61, 64, 65, 66, 67, 68, 71, 72, 74, 75, 78, 79, 80, 82, 86, 87, 89, 90, 91, 93, 102, 105, 106, 108, 109, 110, 111, 116, 117, 118, 121, 124

Offset: 1

Author

N. J. A. Sloane, Nov 15 2011

Keywords

• nonn
• base

Links

• T. D. Noe, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A119450, A200259 (complement).

Programs

Magma

[ n: n in [1..162] | IsOdd(&+Intseq(NthPrime(n))) ];  // Bruno Berselli, Nov 15 2011

Mathematica

Select[Range[1000], OddQ[Total[IntegerDigits[Prime[#]]]] &] (* T. D. Noe, Nov 21 2011 *)

PARI

isok(k) = sumdigits(prime(k)) % 2; \\ Michel Marcus, Jul 03 2021