A217400 Numbers starting with 7.

7, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 700, 701, 702, 703, 704, 705, 706, 707, 708, 709, 710, 711, 712, 713, 714, 715, 716, 717, 718, 719, 720, 721, 722, 723, 724, 725, 726, 727, 728, 729, 730, 731, 732, 733, 734, 735, 736, 737, 738, 739, 740, 741, 742

Offset

1,1

Comments

The lower and upper asymptotic densities of this sequence are 1/63 and 5/36, respectively. - Amiram Eldar, Feb 27 2021

Links

Jeremy Gardiner, Table of n, a(n) for n = 1..1111

Index entries for 10-automatic sequences.

Formula

a(n) = n + (62*10^floor(log_10(9*n-8))-8)/9. - Alan Michael Gómez Calderón, May 17 2023

Mathematica

Select[Range[1000], IntegerDigits[#][[1]] == 7 &] (* T. D. Noe, Oct 02 2012 *)

Crossrefs

Cf. A000870, A011537.

Subsequences include: A045713, A077332, A077683, A106417, A106427.

Cf. A131835, A217394, A217395, A217397, A217398, A217399, A217401, A217402.

Sequence in context: A121351 A302353 A059321 * A077683 A082797 A216994

Adjacent sequences: A217397 A217398 A217399 * A217401 A217402 A217403

Keyword

nonn,base,easy

Author

Jeremy Gardiner, Oct 02 2012

Status

approved