A231551 Position of n in A231550.
0, 1, 2, 3, 4, 7, 6, 5, 8, 15, 14, 9, 12, 11, 10, 13, 16, 31, 30, 17, 28, 19, 18, 29, 24, 23, 22, 25, 20, 27, 26, 21, 32, 63, 62, 33, 60, 35, 34, 61, 56, 39, 38, 57, 36, 59, 58, 37, 48, 47, 46, 49, 44, 51, 50, 45, 40, 55, 54, 41, 52, 43, 42, 53, 64, 127, 126, 65
Offset: 0
Links
Programs
-
Mathematica
Join[{0, 1}, Table[d = Reverse@IntegerDigits[n, 2]; FromDigits[Reverse@Append[FoldList[BitXor, d[[1]], Most@Rest@d], d[[-1]]], 2], {n, 2, 67}]] (* Ivan Neretin, Dec 28 2016 *) -
Python
for n in range(99): bits = [0]*64 orig = [0]*64 l = int.bit_length(int(n)) t = n for i in range(l): bits[i] = orig[i] = t&1 t>>=1 #for i in range(1, l-1): bits[i] ^= orig[i-1] # A231550 for i in range(1, l-1): bits[i] ^= bits[i-1] # A231551 #for i in range(l-1): bits[i] ^= orig[i+1] # A003188 #for i in range(1, l): bits[l-1-i] ^= bits[l-i] # A006068 t = 0 for i in range(l): t += bits[i]< -
R
maxrow <- 8 # by choice b01 <- 0 # b01 is going to be A010059 a <- 1 for(m in 0:maxrow) for(k in 0:(2^m-1)){ b01[2^(m+1)+ k] <- b01[2^m+k] a[2^(m+1)+ k] <- a[2^m+k] + 2^(m+b01[2^(m+1)+ k]) b01[2^(m+1)+2^m+k] <- 1 - b01[2^m+k] a[2^(m+1)+2^m+k] <- a[2^m+k] + 2^(m+b01[2^(m+1)+2^m+k]) } (a <- c(0,a)) # Yosu Yurramendi, Apr 10 2017
-
R
maxblock <- 8 # by choice a <- 1:3 for(n in 4:2^maxblock){ ones <- which(as.integer(intToBits(n)) == 1) nbit <- as.integer(intToBits(n))[1:tail(ones, n = 1)] anbit <- nbit for(i in 2:(length(anbit) - 1)) anbit[i] <- bitwXor(anbit[i], anbit[i-1]) # ?bitwXor a <- c(a, sum(anbit*2^(0:(length(anbit) - 1)))) } (a <- c(0,a)) # Yosu Yurramendi, Apr 25 2021
Comments