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A302782
Inverse permutation to A302781.
3
0, 1, 3, 15, 5, 2, 21, 14, 63, 6, 255, 12, 85, 20, 4, 341, 1023, 62, 4095, 10, 22, 254, 1365, 13, 5461, 86, 60, 16, 16383, 7, 65535, 340, 252, 1022, 26, 48, 21845, 4094, 84, 9, 87381, 23, 262143, 240, 58, 1366, 1048575, 342, 349525, 5460, 1020, 90, 1398101, 61, 250, 19, 4092, 16382, 4194303, 11, 16777215, 65534, 42
OFFSET
1,3
FORMULA
a(n) = A302845(A052331(n)).
PROG
(PARI)
up_to = 8192;
v050376 = vector(up_to);
ispow2(n) = (n && !bitand(n, n-1));
i = 0; for(n=1, oo, if(ispow2(isprimepower(n)), i++; v050376[i] = n); if(i == up_to, break));
A052331(n) = { my(s=0, e); while(n > 1, fordiv(n, d, if(((n/d)>1)&&ispow2(isprimepower(n/d)), e = vecsearch(v050376, n/d); if(!e, print("v050376 too short!"); return(1/0)); s += 2^(e-1); n = d; break))); (s); };
A006068(n)= { my(s=1, ns); while(1, ns = n >> s; if(0==ns, break()); n = bitxor(n, ns); s <<= 1; ); return (n); } \\ From A006068
A057300(n) = { my(t=1, s=0); while(n>0, if(1==(n%4), n++, if(2==(n%4), n--)); s += (n%4)*t; n >>= 2; t <<= 2); (s); };
A163355(n) = if(!n, n, my(i = (#binary(n)-1)\2, f = 4^i, d = (n\f)%4, r = (n%f)); if(((1==d)&&!(i%2))||((2==d)&&(i%2)), f+A163355(A057300(r)), if(3==d, f+f+A163355(A057300(r)), (3*f)+A163355(f-1-r))));
CROSSREFS
Cf. A302781 (inverse).
Sequence in context: A369370 A009215 A274078 * A375889 A088558 A212203
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 14 2018
STATUS
approved