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Record values in A130971.
4

%I #7 Mar 31 2012 13:21:09

%S 2,3,13,23,41,47,73,97,131,163,191,193,239,277,307,353,373,379,449,

%T 487,601,631,643,709,761,811,823,881,911,1013,1033,1091,1109,1193,

%U 1213,1217,1291,1301,1319,1373,1423,1447,1483,1601,1621,1721,1823,1867,1873,1901,4021,5011,266111,4294978733

%N Record values in A130971.

%C Are the values A103150(53)=266111 and A103150(54)=4294978733 correct? -- Antti Karttunen, Jun 19 2007.

%H Ray Chandler, <a href="/A103150/b103150.txt">Table of n, a(n) for n=1..59</a>

%F a(n) = A130971(A130972(n)).

%e a(53) = 266111 = 2^18 - 3967, where 3967 = prime(549).

%e a(54) = 4294978733 = 2^32 - 11437, where 11437 = prime(1379).

%e a(55) = 37778931862957161731461 = 2^75 - 21893, where 21893 = prime(2456).

%e a(56) = 37778931862957161765331 = 2^75 - 55763, where 55763 = prime(5658).

%e a(57) = 2787593149816327892691964784081045188361473 = 2^141 - 113921, where 113921 = prime(10782).

%e a(58) = 2^835 - 983063, where 983063 = prime(77280). (252 digits)

%e a(59) = 2^1322 - 3993547, where 3993547 = prime(282738). (398 digits)

%e a(60) = 2^5945 - 42565109, where 42565109 = prime(2579884). (1790 digits)

%e a(61) = 2^16116 - 52274777, where 52274777 = prime(3129277). (4852 digits)

%t pmin = 0; pm0 = 2^16384; mpm =0; ppm = 0; mcm = 0; pcm = 0; p = 1; While[pmin < pm0, pmin = pm0; = 0; nu2 = 1; cm = nu2 - p; cp = nu2 + p; While[(n < 16383) && (cm < pmin), If[(cp < pmin) && PrimeQ[cp], pmin = cp]; acm = Abs[cm]; If[(mpm < pmin) && PrimeQ[p], mpm = pmin; ppm = p; Save["pinc.txt", {mpm, ppm}]]; p = p + 2]

%Y Cf. A103149, A102632.

%K nonn

%O 1,1

%A _Lei Zhou_, Feb 05 2005

%E Edited, Scheme-code added and starting offset changed from 0 to 1 by _Antti Karttunen_, Jun 19 2007

%E Confirmed a(1)-a(54), extend to a(61) by _Ray Chandler_, Aug 06 2010