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a(n) is the first digit of prime(n) minus the sum of the other digits.
1

%I #49 Oct 04 2024 14:34:41

%S 2,3,5,7,0,-2,-6,-8,-1,-7,2,-4,3,1,-3,2,-4,5,-1,6,4,-2,5,-1,2,0,-2,-6,

%T -8,-3,-8,-3,-9,-11,-12,-5,-11,-8,-12,-9,-15,-8,-9,-11,-15,-17,0,-3,

%U -7,-9,-4,-10,-3,-4,-10,-7,-13

%N a(n) is the first digit of prime(n) minus the sum of the other digits.

%C Absolute terms are the same as A042939.

%H Harvey P. Dale, <a href="/A185107/b185107.txt">Table of n, a(n) for n = 1..1000</a>

%t Table[With[{id=IntegerDigits[Prime[n]]},id[[1]]-Total[Rest[id]]],{n,60}] (* _Harvey P. Dale_, Oct 04 2024 *)

%o (PARI) a(n) = {digs = digits(prime(n)); digs[1] - sum(i=2, #digs, digs[i]);} \\ _Michel Marcus_, Aug 30 2013

%Y Cf. A000040, A042939, A007605.

%K sign,base,less

%O 1,1

%A _Dario Piazzalunga_, Dec 27 2012

%E a(38) corrected by _Michel Marcus_, Jun 14 2022