A372045 Positions of records in A030000.

0, 7, 11, 22, 50, 61, 78, 100, 121, 122, 127, 155, 263, 548, 1000, 1002, 1003, 1016, 1559, 1583, 1877, 3087, 9634, 10001, 10029, 10199, 10620, 25672, 100002, 100005, 100085, 100116, 100457, 100956, 101597, 101624, 114323, 191974, 1000004, 1000006, 1000055, 1000227, 1000517, 1000717, 1000728, 1027986, 1098714, 1127153, 1429848, 3659369

Offset: 1

Author

Paolo Xausa, Apr 17 2024

Keywords

• nonn
• base

Examples

			From _David A. Corneth_, Apr 17 2024: (Start)
0 is a term as it is the least nonnegative integer and A030000(0) = 10.
7 is a term after 0 as 7 is the first number that is first seen at a k such that 2^k contains 7 as a substring (namely at k = 15). (End)
		

Crossrefs

Cf. A030000, A371887, A372044.

Programs

Mathematica

d2k[k_] := d2k[k] = IntegerString[2^k];
A030000[n_] := Block[{d = IntegerString[n], k = -1}, While[StringFreeQ[d2k[++k], d]]; k];
Block[{upto = 10000, n = -1, a, r = -1}, Reap[While[++n <= upto, If[(a = A030000[n]) > r, r = a; Sow[n]]]][[2, 1]]]

Extensions

More terms from David A. Corneth, Apr 17 2024