A085402 a(n) = abs(A085401(n-1) - A085401(n)).

2, 3, 13, 5, 7, 11, 19, 17, 23, 29, 37, 31, 41, 43, 47, 59, 53, 61, 67, 71, 73, 79, 83, 89, 107, 97, 101, 103, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 199, 191, 193, 197, 211, 223, 227, 233, 229, 239, 251, 241, 257, 269, 263, 271, 277

Offset

1,1

Comments

Primes used in constructing the terms of A085401. Except for an initial part of the sequence and occasional local rearrangements later on (e.g. 199,191,193,197; 1063,1049,1051,1061) the primes appear in ascending order.

Links

Table of n, a(n) for n=1..59.

Example

a(8) = abs(A085401(7) - A085401(8)) = abs(37 - 20) = 17.

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

Cf. A085401, A085400.

Sequence in context: A342667 A191000 A361831 * A085400 A067523 A035515

Adjacent sequences: A085399 A085400 A085401 * A085403 A085404 A085405

Keyword

nonn

Author

Klaus Brockhaus, Jun 28 2003

Status

approved