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A217399
Numbers starting with 6.
13
6, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 600, 601, 602, 603, 604, 605, 606, 607, 608, 609, 610, 611, 612, 613, 614, 615, 616, 617, 618, 619, 620, 621, 622, 623, 624, 625, 626, 627, 628, 629, 630, 631, 632, 633, 634, 635, 636, 637, 638, 639, 640, 641, 642
OFFSET
1,1
COMMENTS
The lower and upper asymptotic densities of this sequence are 1/54 and 10/63, respectively. - Amiram Eldar, Feb 27 2021
FORMULA
a(n) = n + (53*10^floor(log_10(9*n-8))-8)/9. - Alan Michael Gómez Calderón, May 17 2023
MAPLE
seq(seq(6*10^n+k, k=0..10^n-1), n=0..3); # Robert Israel, May 08 2017
MATHEMATICA
Select[Range[1000], IntegerDigits[#][[1]] == 6 &] (* T. D. Noe, Oct 02 2012 *)
PROG
(PARI) isok(n) = digits(n)[1] == 6; \\ Michel Marcus, May 08 2017
(GAP) Flat(List([0..2], n->List([0..10^n-1], k->6*10^n+k))); # Muniru A Asiru, Nov 21 2018
(Magma) [n: n in [1..1600] | Intseq(n)[#Intseq(n)] eq 6]; // Vincenzo Librandi, Nov 24 2018
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Jeremy Gardiner, Oct 02 2012
STATUS
approved