|
|
|
|
0, 1, 1, 5, 1, 7, 8, 31, 1, 9, 10, 41, 12, 59, 71, 247, 1, 13, 14, 61, 16, 87, 103, 371, 18, 113, 131, 493, 167, 719, 886, 2927, 1, 15, 16, 71, 18, 101, 119, 433, 20, 131, 151, 575, 191, 837, 1028, 3421, 24, 191, 215, 859, 263, 1241, 1504, 5153, 311, 1623, 1934, 6871, 2556, 10117, 12673, 40361, 1, 19, 20, 91, 22, 129
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,4
|
|
LINKS
|
|
|
FORMULA
|
|
|
MATHEMATICA
|
Array[If[# < 2, 0, # Total[#2/#1 & @@@ FactorInteger[#]]] &[Times @@ Prime@ Flatten@ Position[Reverse@ IntegerDigits[#, 2], 1]] &, 70, 0] (* Michael De Vlieger, Apr 08 2021 *)
|
|
PROG
|
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };
|
|
CROSSREFS
|
|
|
KEYWORD
|
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|