A284923 Numbers with digits 2 and 9 only.

2, 9, 22, 29, 92, 99, 222, 229, 292, 299, 922, 929, 992, 999, 2222, 2229, 2292, 2299, 2922, 2929, 2992, 2999, 9222, 9229, 9292, 9299, 9922, 9929, 9992, 9999, 22222, 22229, 22292, 22299, 22922, 22929, 22992, 22999, 29222, 29229, 29292, 29299, 29922, 29929

Offset

1,1

Links

Table of n, a(n) for n=1..44.

Mathematica

Select[Range[30000], SubsetQ[{2, 9}, Sort[DeleteDuplicates[IntegerDigits[#]]]] &] (* Stefano Spezia, Aug 06 2025 *)

Prog

(Magma) [n: n in [1..100000] | Set(IntegerToSequence(n, 10)) subset {2, 9}];

Crossrefs

Prime terms are in A020460.

Numbers with digits 2 and k only for k = 0 - 1 and 3 - 9: A169965 (k = 0), A007931 (k = 1), A032810 (k = 3), A284920 (k = 4), A072961 (k = 5), A284632 (k = 6), A284921 (k = 7), A284922 (k = 8), this sequence (k = 9).

Sequence in context: A248116 A259702 A377793 * A343850 A235707 A056105

Adjacent sequences: A284920 A284921 A284922 * A284924 A284925 A284926

Keyword

nonn,base

Author

Jaroslav Krizek, Apr 06 2017

Status

approved