(define (log2 number)
  (/ (log number) (log 2)))

> (log2 1024)
10.0
> (log2 8)
3.0
> (log2 16)
4.0

> (map log2 '(2 3 4 5 6 7 8 16 32 64 128))
(1.0
 1.5849625007211563
 2.0
 2.321928094887362
 2.584962500721156
 2.807354922057604
 3.0
 4.0
 5.0
 6.0
 7.0)

(map log2 '(2 4 8 16 32 64 128 256 1024 2048 4096))
(1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 10.0 11.0 12.0)

(define (log16 number)            Base 16 = hexadecimal
  (/ (log number) (log 16)))

> (map log16 '(2 4 8 16 32 64 128 256 1024 2048 4096))
(0.25 0.5 0.75 1.0 1.25 1.5 1.75 2.0 2.5 2.75 3.0)

> (log16 (expt 16 10))
10.0

> (expt 16 10)
1099511627776

> (sumOfFunction log2 '(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20))
61.07738392090622

> (map log2 '(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20))
(0
 1.0
 1.5849625007211563
 2.0
 2.321928094887362
 2.584962500721156
 2.807354922057604
 3.0
 3.1699250014423126
 3.3219280948873626
 3.4594316186372978
 3.5849625007211565
 3.700439718141092
 3.8073549220576037
 3.9068905956085187
 4.0
 4.08746284125034
 4.169925001442312
 4.247927513443585
 4.321928094887363)

(define (sumOfFunction function myList)
  (apply + (map function myList)))

(define (log2 number)
  (/ (log number) (log 2)))

> (define log2sOneToTwenty (map log2 '(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 
16 17 18 19 20)))

> (sumOfFunction floor log2sOneToTwenty)
54.0

> (sumOfFunction ceiling log2sOneToTwenty)
69.0

> (sumOfFunction + log2sOneToTwenty)
61.07738392090622

> (expt 2 61.07738392090622)
2432902008176640500          <------------ 2 raised to 61.07738th power

> (factorial 20)
2432902008176640000          <----------- 20 factorial

2432902008176640500          <------------ 2 raised to 61.07738th power
2432902008176640000          <----------- 20 factorial