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A284460
Permutation of the positive integers: this permutation transforms the enumeration system of positive irreducible fractions A245327/A245328 into the enumeration system A002487/A002487' (Calkin-Wilf), and A020651/A020650 (Yu-Ting inverted) into A162911/A162912(Drib).
4
1, 2, 3, 6, 5, 4, 7, 14, 13, 8, 11, 10, 9, 12, 15, 30, 29, 24, 27, 18, 17, 20, 23, 22, 21, 16, 19, 26, 25, 28, 31, 62, 61, 56, 59, 50, 49, 52, 55, 38, 37, 32, 35, 42, 41, 44, 47, 46, 45, 40, 43, 34, 33, 36, 39, 54, 53, 48, 51, 58, 57, 60, 63
OFFSET
1,2
COMMENTS
The inverse permutation is A284459.
FORMULA
a(n) = A231550(A258996(n)) = A092569(A231550(n)), n > 0 . - Yosu Yurramendi, Apr 10 2017
PROG
(R)
maxrow <- 4 # by choice
a <- 1
b01 <- 1
for(m in 0:maxrow){
b01 <- c(b01, rep(1, 2^(m+1))); b01[(2^(m+1)+2^m-2^(m-1)):(2^(m+1)+2^m+2^(m-1)-1)] <- 0
for(k in 0:(2^m-1)){
a[2^(m+1) + k] <- a[2^m + k] + 2^(m + b01[2^(m+1) + k])
a[2^(m+1) + 2^m + k] <- a[2^m + k] + 2^(m + b01[2^(m+1) + 2^m + k])
}}
a
# Yosu Yurramendi, Mar 28 2017
KEYWORD
nonn
AUTHOR
Yosu Yurramendi, Mar 28 2017
STATUS
approved