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Common differences of the arithmetic progressions corresponding to A095181.
1

%I #19 Sep 18 2020 13:59:21

%S 1,11,1,7,11,47,25,17,52,23,73,97,41,61,151,131,157,139,89,239,451,

%T 281,371,509,283,661,263,841,587,839,1339,671,1171,499,1283,289,1903,

%U 743,1621,2609,359,2533,1751,2993,1153,6211,881,3011,3613,3631,2771,6869,1553,5801,1159,4603,2311,1141,9097

%N Common differences of the arithmetic progressions corresponding to A095181.

%C How many terms are even?

%H Jean-François Alcover, <a href="/A095193/b095193.txt">Table of n, a(n) for n = 2..200</a>

%F a(n) = (A095182(n) - prime(n))/(n-1). [_R. J. Mathar_, Oct 14 2010]

%t (* b = A095182 *) b[n_] := For[r = 1, True, r++, ro = Table[Prime[n] + k*r, {k, 0, n - 1}]; If[AllTrue[Rest[ro], CompositeQ[#] && ! Divisible[#, Prime[n]] &], Return[ro[[-1]]]]];

%t a[n_] := (b[n] - Prime[n])/(n - 1);

%t Table[a[n], {n, 2, 60}] (* _Jean-François Alcover_, Jan 15 2018, after _R. J. Mathar_ *)

%Y Cf. A095181.

%K nonn

%O 2,2

%A _Amarnath Murthy_, Jun 04 2004

%E Extended beyond a(6) by _R. J. Mathar_, Oct 14 2010

%E a(43)-a(60) by _Jean-François Alcover_, Jan 15 2018