A085434 n-th even number not a power of 2 whose largest and smallest factors do not add or subtract to a twin prime.

46, 74, 94, 106, 134, 158, 166, 178, 194, 226, 254, 262, 314, 326, 334, 346, 422, 446, 466, 502, 514, 526, 554, 586, 614, 634, 662, 674, 706, 718, 734, 746, 758, 766, 778, 794, 802, 818, 878, 886, 898, 914, 934, 958, 974, 982, 998, 1006, 1018, 1082, 1094

Offset

6,1

Comments

The density of these numbers approach 0 as n approaches oo.

Links

Table of n, a(n) for n=6..56.

Prog

(PARI) maxpmmintwin(n) = { c=0; forprime(p=3, n, if(!isprime(p-2) & !isprime(p+2), print1(p+p", "); c++); ); print(); print(c" "c/n+.0) }

Crossrefs

Cf. A052369, A056608.

Sequence in context: A101577 A051413 A167283 * A245372 A020351 A113691

Adjacent sequences: A085431 A085432 A085433 * A085435 A085436 A085437

Keyword

easy,nonn

Author

Cino Hilliard, Aug 13 2003

Status

approved