A241146 Least number k such that k and n*k share at least one digit.

1, 10, 5, 10, 5, 2, 5, 10, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 10, 1, 9, 5, 10, 5, 2, 5, 6, 5, 5, 1, 10, 5, 10, 4, 2, 4, 10, 5, 10, 1, 10, 5, 3, 3, 2, 5, 8, 5, 5, 1, 10, 5, 7, 5, 2, 5, 10, 5, 2, 1, 2, 2, 2, 5, 2, 5, 7, 5, 5, 1, 10, 5, 10, 5, 2, 3, 3, 3, 10, 1, 7, 5, 10, 4, 2, 4, 9, 5, 5, 1, 10, 5, 6, 5, 2, 5, 8, 5, 1

Offset

1,2

Comments

\ 10^3...10^4....10^5.....10^6......10^7.......10^8........10^9

k\

.1..272...3440...40952...468560...5217032...56953280...612579512

.2..149...1613...16837...171325...1710773...16837421...163825573

.3...87...1091...12038...124060...1225493...11762254...110573419

.4...62....710....7196....68280....621670....5502346....47710882

.5..248...1914...14674...111846....848318....6407338....48220222

.6...26....246....2087....16749....129768.....980911.....7280424

.7...36....323....2587....19368....138838.....966609.....6591845

.8...20....156....1095.....7199.....45386.....277985.....1667513

.9...22....162....1028.....6055.....34178.....187661.....1010240

10...78....345....1506.....6558.....28544.....124195......540370

The sequence of numbers whose first digit is k:

.1: 1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 31, 41, 51, 61, 71, 81, 91, 100, …, . A011531?

.2: 6, 26, 36, 46, 56, 60, 62, 63, 64, 66, 76, 86, 96, 206, 226, 236, 246, 256, 260, 262, …, .

.3: 44, 45, 77, 78, 79, 244, 245, 277, 278, 279, 344, 345, 377, 378, 379, 434, 435, 437, 438, …, .

.4: 35, 37, 85, 87, 235, 237, 285, 287, 335, 337, 350, 352, 353, 354, 355, 357, 358, 359, 365, …, .

.5: 3, 5, 7, 9, 23, 25, 27, 29, 30, 33, 39, 43, 47, 49, 50, 53, 55, 57, 59, 65, 67, 69, 70, 73, …, .

.6: 28, 94, 228, 268, 272, 274, 280, 282, 294, 328, 394, 428, 494, 528, 594, 694, 728, 828, 894, …, .

.7: 54, 68, 82, 248, 252, 254, 382, 388, 392, 398, 468, 482, 532, 534, 538, 540, 542, 554, 568, …, .

.8: 48, 98, 232, 234, 298, 348, 480, 484, 498, 548, 598, 698, 732, 734, 748, 848, 898, 980, 984, …, .

.9: 22, 88, 220, 222, 288, 322, 324, 332, 422, 488, 522, 552, 588, 658, 688, 722, 880, 884, 888, …, .

10: 2, 4, 8, 20, 24, 32, 34, 38, 40, 42, 52, 58, 72, 74, 80, 84, 92, 200, 202, 204, 208, 224, …, .

Links

Table of n, a(n) for n=1..100.

Formula

If a(n) = k so does a(10n).

Mathematica

f[n_] := Block[{k = 1}, While[ Intersection[ IntegerDigits[k], IntegerDigits[n*k]] == {}, k++]; k]; Array[f, 100]

Crossrefs

Cf. A129845, A129846, A129848, A241141, A241142, A241143, A241144, A241145.

Sequence in context: A030071 A147653 A152611 * A296420 A078267 A083950

Adjacent sequences: A241143 A241144 A241145 * A241147 A241148 A241149

Keyword

nonn,base,easy

Author

Robert G. Wilson v, Apr 16 2014

Status

approved