A306689 Integers m with decimal expansion m = abc...z such that m is a multiple of both az and za; z may not be zero.

11, 22, 33, 44, 55, 66, 77, 88, 99, 121, 242, 363, 484, 1001, 1092, 1111, 1207, 1221, 1275, 1331, 1441, 1458, 1512, 1551, 1661, 1729, 1771, 1785, 1881, 1932, 1991, 2002, 2112, 2184, 2222, 2332, 2442, 2552, 2662, 2772, 2882, 2992, 3003, 3276, 3333, 3663, 3993, 4004, 4032

Offset

1,1

Comments

Every power of 11 is a term. - N. J. A. Sloane, Jul 14 2019

Links

Alois P. Heinz, Table of n, a(n) for n = 1..10000

Example

1512 is in the list since 12*126=1512 and 21*72=1512.

Prog

(Python)
for a in range(1, 1000):
   for b in range (1, 10):
      numb = 10*a + b
      f = int(str(numb)[0])
      first = 10*f + b
      last = 10*b + f
      if numb %  first == 0 and numb % last == 0 :
         print(numb, end=', ')

Crossrefs

Cf. A073729.

Sequence in context: A302438 A068900 A083852 * A382337 A241899 A226468

Adjacent sequences: A306686 A306687 A306688 * A306690 A306691 A306692

Keyword

nonn,base

Author

Reiner Moewald, Mar 05 2019

Status

approved