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A085400
a(n) = abs(A085061(n-1) - A085061(n)).
2
2, 3, 13, 5, 7, 17, 19, 11, 23, 29, 31, 41, 37, 43, 47, 53, 59, 61, 67, 71, 83, 73, 79, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 157, 151, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277
OFFSET
1,1
COMMENTS
Primes used in constructing the terms of A085061. Except for an initial part of the sequence and occasional transpositions later on (e.g. 157,151; 691,683) the primes appear in ascending order.
EXAMPLE
a(8) = abs(A085061(7) - A085061(8)) = abs(23 - 34) = 11.
PROG
(PARI) {in(n, v)=local(j, s, b); j=1; s=matsize(v)[2]; b=1; while(b&&j<=s, if(n==v[j], b=0, j++)); !b}
{a=1; v=[]; for(n=1, 60, p=2; t=1; while(t>0, if(in(p, v), p=nextprime(p+1), if(!isprime(2*a+p), t=0; b=a+p, if(p<a&&!isprime(2*a-p), t=0; b=a-p, p=nextprime(p+1))))); v=concat(v, p); print1(p, ", "); a=b)}
CROSSREFS
Sequence in context: A191000 A361831 A085402 * A067523 A035515 A317716
KEYWORD
nonn
AUTHOR
Klaus Brockhaus, Jun 28 2003
STATUS
approved