OFFSET
1,1
COMMENTS
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..10000
FORMULA
EXAMPLE
Seen as an irregular triangle T(n,k) of rows n where P(n) | T(n,k)
2: 24;
3: 120, 180;
4: 840, 1260, 1680;
5: 9240, 13860, 18480, 27720;
6: 120120, 180180, 240240, 360360, 480480;
7: 2042040, 3063060, 4084080, 6126120, 8168160;
...
MATHEMATICA
P = 2; nn = 10;
s = Select[Range[4, Prime[nn], 2],
Or[IntegerQ@ Log2[#],
And[Union@ Differences@ PrimePi[#1] == {1},
AllTrue[Differences[#2], # <= 0 &]] & @@
Transpose@ FactorInteger[#]] &];
Table[P *= Prime[n];
P*TakeWhile[s, # <= Prime[n + 1] &], {n, 2, nn}] // Flatten
CROSSREFS
KEYWORD
nonn
AUTHOR
Michael De Vlieger, Jan 28 2024
STATUS
approved