A159774 Least number m, written in base n, such that m/2 is obtained merely by shifting the leftmost digit of m to the right end, and 2m by shifting the rightmost digit of m to the left end, digits defined in base n.

1012, 102, 102342, 1031345242, 103524563142, 1042, 10467842, 105263157894736842, 316, 10631694842

Offset

3,1

Comments

10(b2) and 31(b5) do not both halve and double by rotations. No 2-digit answer can meet the description, so the sequence begins with a base 3 value.

Links

Table of n, a(n) for n=3..12.

W. A. Hoffman III, Algorithm to compute terms.

Example

1042(b8)/2 = 421(b8) and 1042(b8)*2 = 2104(b8)
316 (base 11) = 380 (base 10), 163 (base 11) = 190 (base 10), 631 (base 11) = 760 (base 10).

Crossrefs

Cf. A092697, A097717, A094224, A094676, A158877.

See A147514 for these numbers written in base 10.

Sequence in context: A291962 A094946 A158877 * A072140 A080467 A023058

Adjacent sequences: A159771 A159772 A159773 * A159775 A159776 A159777

Keyword

base,nonn,fini,full

Author

William A. Hoffman III (whoff(AT)robill.com), Apr 21 2009

Extensions

Offset corrected by N. J. A. Sloane, Apr 23 2009

a(11) corrected. To indicate that terms from base n=13 on need digits larger than 9, keywords fini, full added. - Ray Chandler and R. J. Mathar, Apr 23 2009

Edited by Ray Chandler, May 02 2009

Status

approved