A096450 - OEIS

%I #7 Apr 19 2016 01:07:34

%S 7,29,37,61,89,101,107,113,131,151,181,239,251,271,397,421,443,463,

%T 479,491,503,557,569,577,601,743,757,787,857,863,881,887,1291,1511,

%U 1531,1549,1609,1657,1667,1693,1699,1861,1987,1997,2003,2017,2053,2377,2393

%N Primes p such that the number of primes q, 7 <= q < p, congruent to 1 or 2 mod 5, is equal to the number of such primes congruent to 3 or 4 mod 5.

%C First term prime(4) = 7 is placed on 0th row.

%C If prime(n-1) = 1 or 2 mod 5 is on k-th row then we put prime(n) on (k-1)-st row.

%C If prime(n-1) = -1 or -2 mod 5 is on k-th row then we put prime(n) on (k+1)-st row.

%C This process produces the following array of prime numbers:

%C 31, 97, ... row -1

%C 7, 29, 37, 61, 89, 101, ... row 0 (this sequence)

%C 11, 17, 23, 41, 47, 59, 67, 83, ... row 1 (A096454)

%C 13, 19, 43, 53, 71, 79, ... row 2 (A096455)

%C 73, ...

%Y Cf. A096448-A096455.

%K nonn,easy

%O 1,1

%A _Yasutoshi Kohmoto_, Aug 12 2004

%E More terms and better definition from _Joshua Zucker_, May 21 2006