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A175075 Primes q with result 2 under iterations of {r mod (max prime p < r)} starting at r = q. 4

%I

%S 2,5,7,13,19,31,43,61,73,103,109,139,151,181,193,199,229,241,271,283,

%T 313,349,421,433,463,523,571,601,619,643,661,811,823,829,859,883,1021,

%U 1033,1051,1063,1093,1153,1231,1279,1291,1303,1321,1429,1453,1483,1489

%N Primes q with result 2 under iterations of {r mod (max prime p < r)} starting at r = q.

%C a(1) = 2, a(n) = A006512(n-1) for 2 <= n <= 82, a(83) = 2999. Sequence is the union of A006512 and A175080. Subsequence of A175072. Primes q with some results of {2, 28, 36, 52, 58, 66, ... } under first step of iteration of {r mod (max prime p < r)} starting at r = q, i.e. number 2 and primes q such that difference q and previous prime is equal to some of the values 2, 28, 36, 52, 58, 66, ...

%F A175072 \ A175076. [From _Jaroslav Krizek_, Jan 30 2010; A-number corrected by _R. J. Mathar_, Sep 25 2010]

%e Iteration procedure for a(5) = 19: 19 mod 17 = 2. Iteration procedure for a(83) = 2999: 2999 mod 2971 = 28, 28 mod 23 = 5, 5 mod 3 = 2.

%t fQ[p_] := Block[{r = p}, While[r > 2, r = Mod[r, NextPrime[r, -1]]]; r == 2]; Select[ Prime@ Range@ 253, fQ] (* _Robert G. Wilson v_, Aug 09 2010 *)

%K nonn

%O 1,1

%A _Jaroslav Krizek_, Jan 23 2010

%E More terms from _Robert G. Wilson v_, Aug 09 2010

%E A175080 inserted in comment - _R. J. Mathar_, Sep 25 2010

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Last modified September 28 02:07 EDT 2020. Contains 337392 sequences. (Running on oeis4.)