|
| |
|
|
A048268
|
|
Smallest palindrome greater than n in bases n and n+1.
|
|
4
| |
|
|
6643, 10, 46, 67, 92, 121, 154, 191, 232, 277, 326, 379, 436, 497, 562, 631, 704, 781, 862, 947, 1036, 1129, 1226, 1327, 1432, 1541, 1654, 1771, 1892, 2017, 2146, 2279, 2416, 2557, 2702, 2851, 3004, 3161, 3322, 3487, 3656, 3829, 4006, 4187, 4372, 4561
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 2,1
|
|
|
FORMULA
| a(n) = 2n^2+3n+2 for n >= 4 (which is (232) in base n and (1n1) in base n+1)
|
|
|
EXAMPLE
| a(14)= 2*14^2+3*14+2=436, which is (232) in base 14 and (1E1) in base 15
|
|
|
MATHEMATICA
| Do[ k = n + 2; While[ RealDigits[ k, n + 1 ][ [ 1 ] ] != Reverse[ RealDigits[ k, n + 1 ][ [ 1 ] ] ] || RealDigits[ k, n ][ [ 1 ] ] != Reverse[ RealDigits[ k, n ][ [ 1 ] ] ], k++ ]; Print[ k ], {n, 2, 75} ]
palQ[n_Integer, base_Integer] := Block[{idn = IntegerDigits[n, base]}, idn == Reverse[idn]]; f[n_] := Block[{k = n + 2}, While[ !palQ[k, n] || !palQ[k, n + 1], k++ ]; k]; Table[ f[n], {n, 2, 48}] (from Robert G. Wilson v Sep 29 2004)
|
|
|
CROSSREFS
| Cf. A048269, A060792, A097928, A097929, A097930, A097931, A099145, A099146, A029965, A029966, A099147, A099153.
Sequence in context: A174590 A178213 A196510 * A043634 A060792 A119519
Adjacent sequences: A048265 A048266 A048267 * A048269 A048270 A048271
|
|
|
KEYWORD
| nonn,easy
|
|
|
AUTHOR
| Ulrich Schimke (ulrschimke(AT)aol.com)
|
|
|
EXTENSIONS
| More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 14 2000
|
| |
|
|
