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A193307
Number of 'Reverse and Subtract' steps needed to reach 0, or -1 if never reaches 0, using base -1+i and subtracting the original number from the reversed.
2
0, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, -1, 2, 15, -1, 1, -1, 1, -1, -1, -1, 1, -1, -1, -1, 3, -1, 1, -1, 3, -1, 1, -1, 1, -1, 3, 2, -1, -1, 15, -1, -1, -1, -1, -1, 1, -1, 3, -1, -1, -1, 1, -1, 7, 2, -1, 2, -1, -1, -1, -1, -1, -1, 1, 14, 1, -1, -1, 6, -1, -1
OFFSET
0,13
LINKS
W. J. Gilbert, Arithmetic in Complex Bases, Mathematics Magazine, Vol. 57, No. 2 (Mar., 1984), pp. 77-81.
EXAMPLE
Decimal 12 is 1100 in binary, which is 2+0i using complex base -1+i. Reversing 1100 gives 0011, or 0+i. Subtracting the original number from the reversed results in -2+i, or 11111 using the complex base. Its reversal is the same, so subtracting them gives 0. Decimal 12 took 2 steps to reach 0, so a(12) = 2.
CROSSREFS
Cf. A193239 (number of steps needed to reach a palindrome with complex base -1+i).
Cf. A193306 (number of 'Reverse and Subtract' steps needed to reach 0, or -1 if never reaches 0, using base -1+i and subtracting the reversed number from the original).
Sequence in context: A106484 A228342 A027739 * A331511 A201050 A299321
KEYWORD
sign,base
AUTHOR
Kerry Mitchell, Jul 22 2011
STATUS
approved