|
| |
|
|
A134694
|
|
a(0) = 2; a(n) = least prime p such that p >= a(n-1) + 2^n
|
|
0
| |
|
|
2, 5, 11, 19, 37, 71, 137, 269, 541, 1061, 2087, 4139, 8237, 16433, 32831, 65599, 131143, 262217, 524369, 1048661, 2097257, 4194409, 8388733, 16777381, 33554639, 67109071, 134217943, 268435697, 536871157, 1073742073, 2147483929
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,1
|
|
|
COMMENTS
| Primes separated by at least successive powers of 2.
|
|
|
EXAMPLE
| a(0) = 2 (by definition)
a(1) = 5 because 5 is the least prime >= 4 = 2 + 2^1
a(2) = 11 because 11 is the least prime >= 9 = 5 + 2^2
a(3) = 19 because 19 is the least prime >= 19 = 11 + 2^3
|
|
|
MATHEMATICA
| a = {2}; Do[i = a[[ -1]]+2^n; While[ !PrimeQ[i], i++ ]; AppendTo[a, i], {n, 1, 50}]; a - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Jan 28 2008
|
|
|
CROSSREFS
| Cf. A000040.
Sequence in context: A084572 A040105 A156768 * A121606 A166164 A097008
Adjacent sequences: A134691 A134692 A134693 * A134695 A134696 A134697
|
|
|
KEYWORD
| easy,nonn
|
|
|
AUTHOR
| Walter G. Carlini (wgcarlini(AT)charter.net), Jan 27 2008
|
|
|
EXTENSIONS
| More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Jan 28 2008
|
| |
|
|
