|
|
A171566
|
|
Primes p such that 2*p-3 and 2*(2*p-3)-3 are primes (First member of a primes in a 2*p-3 double progression).
|
|
1
|
|
|
3, 5, 7, 13, 17, 23, 37, 43, 97, 107, 113, 127, 157, 167, 223, 283, 317, 373, 433, 547, 563, 587, 617, 647, 743, 757, 773, 937, 1123, 1277, 1297, 1423, 1483, 1487, 1543, 1583, 1597, 1667, 1697, 1823, 1913, 1933, 1973, 2137, 2143, 2243, 2333, 2437, 2467
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
REFERENCES
|
Mohammad K. Azarian, Double Progression, Problem 231, Math Horizons, Vol. 16, Issue 4, April 2009, p. 31. Solution published in Vol. 17, Issue 2, November 2009, p. 32.
|
|
LINKS
|
|
|
EXAMPLE
|
2*3-3=3, 2*5-3=7; 2*7-3=11, 2*7-3=11; 2*11-3=19,..
|
|
MATHEMATICA
|
Select[Prime[Range[7! ]], PrimeQ[2*#-3]&&PrimeQ[2*(2*#-3)-3]&]
Select[Prime[Range[400]], AllTrue[{2#-3, 4#-9}, PrimeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 04 2021 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|