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A200261 a(n) = 1 iff n-th prime has an even digit sum. 4

%I #14 Mar 20 2023 13:05:43

%S 1,0,0,0,1,1,1,1,0,0,1,1,0,0,0,1,1,0,0,1,1,1,0,0,1,1,1,1,1,0,1,0,0,0,

%T 1,0,0,1,1,0,0,1,0,0,0,0,1,0,0,0,1,1,0,1,1,0,0,1,1,0,0,1,1,0,0,0,0,0,

%U 1,1,0,0,1,0,0,1,1,0,0,0,1,0,1,1,1,0

%N a(n) = 1 iff n-th prime has an even digit sum.

%C Characteristic function of A200259.

%H T. D. Noe, <a href="/A200261/b200261.txt">Table of n, a(n) for n = 1..1000</a>

%t Table[1 - Mod[Total[IntegerDigits[Prime[n]]], 2], {n, 100}] (* _T. D. Noe_, Nov 21 2011 *)

%o (Magma) [IsEven(&+Intseq(NthPrime(n))) select 1 else 0: n in [1..100]]; // _Bruno Berselli_, Nov 15 2011

%Y Cf. A200259, A200263.

%K nonn,base

%O 1

%A _N. J. A. Sloane_, Nov 15 2011

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Last modified April 25 11:36 EDT 2024. Contains 371968 sequences. (Running on oeis4.)