|
|
A090468
|
|
Class 13+ primes.
|
|
7
|
|
|
545587687, 852480757, 1048438561, 1150849009, 1323457987, 1745980517, 1756123441, 1785398401, 1798736161, 1892507347, 1937020021, 2002155601, 2136716521, 2150905573, 2229004913, 2548101601, 2671514917, 2838761021
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
REFERENCES
|
R. K. Guy, Unsolved Problems in Number Theory, A18.
|
|
LINKS
|
|
|
MAPLE
|
For Maple program see Mathar link in A005105.
|
|
MATHEMATICA
|
PrimeFactors[n_Integer] := Flatten[ Table[ #[[1]], {1}] & /@ FactorInteger[n]]; f[n_Integer] := Block[{m = n}, If[m == 0, m = 1, While[ IntegerQ[m/2], m /= 2]; While[ IntegerQ[m/3], m /= 3]]; Apply[Times, PrimeFactors[m] + 1]]; ClassPlusNbr[n_] := Length[ NestWhileList[f, n, UnsameQ, All]] - 3; Prime[ Select[ Range[195000000], ClassPlusNbr[ Prime[ # ]] == 13 &]]
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|