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A253274
Exponent of the highest power of 2 dividing A007497(n).
1
1, 0, 2, 0, 3, 0, 3, 2, 3, 5, 3, 6, 2, 12, 3, 13, 3, 9, 6, 13, 10, 9, 7, 13, 9, 13, 5, 14, 6, 12, 11, 26, 0, 14, 15, 17, 6, 20, 15, 18, 17, 35, 10, 8, 23, 11, 15, 10, 16, 29, 32, 12, 19, 27, 25, 26, 18, 24, 33, 22, 36, 13, 24, 18, 24, 43, 16, 29, 35, 18, 12, 42
OFFSET
1,3
LINKS
FORMULA
a(n) = A007814(A007497(n)).
EXAMPLE
A007497(9) = 168 = 2^3*3*7, so a(n) = 3.
MATHEMATICA
f[1] = 2; f[n_] := f[n] = DivisorSigma[1, f[n - 1]]; Table[IntegerExponent[f[n], 2], {n, 70}] (* Amiram Eldar, Mar 27 2023 *)
CROSSREFS
Sequence in context: A259708 A029220 A249901 * A365920 A337980 A373148
KEYWORD
nonn
AUTHOR
Allan C. Wechsler, May 01 2015
EXTENSIONS
More terms from Michel Marcus, May 01 2015
STATUS
approved