|
| |
|
|
A059761
|
|
Initial primes of Cunningham chains of first type with length exactly 2. Primes in A059453 which survive as primes only one "2p-1 iteration", forming chains of exactly 2 terms.
|
|
14
| |
|
|
3, 29, 53, 113, 131, 173, 191, 233, 239, 251, 281, 293, 419, 431, 443, 491, 593, 641, 653, 659, 683, 743, 761, 809, 911, 953, 1013, 1049, 1103, 1223, 1289, 1499, 1559, 1583, 1601, 1733, 1973, 2003, 2069, 2129, 2141, 2273, 2339, 2351, 2393, 2399, 2543
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
LINKS
| C. K. Caldwell, Cunningham Chains
W. Roonguthai, Yves Gallot's Proth.exe and Cunningham Chains
|
|
|
FORMULA
| {(p-1)/2, p, 2p+1, 4p+3} = {composite, prime, prime, composite}
|
|
|
EXAMPLE
| 53 is here because 26 and 215 are composites,53 and 107 are primes
|
|
|
CROSSREFS
| A023272, A023302, A023330, A005384, A005385, A059452-A059455, A007700.
Sequence in context: A072306 A071150 A107189 * A049437 A171409 A031912
Adjacent sequences: A059758 A059759 A059760 * A059762 A059763 A059764
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Feb 20 2001
|
| |
|
|
