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Powers of 2 with initial digit 8.
2

%I #12 Nov 21 2018 11:27:12

%S 8,8192,8388608,8589934592,8796093022208,

%T 81129638414606681695789005144064,83076749736557242056487941267521536,

%U 85070591730234615865843651857942052864,87112285931760246646623899502532662132736,89202980794122492566142873090593446023921664

%N Powers of 2 with initial digit 8.

%H Muniru A Asiru, <a href="/A320864/b320864.txt">Table of n, a(n) for n = 1..170</a>

%H <a href="/index/Di#divseq">Index to divisibility sequences</a>

%p select(x->"8"=""||x[1],[2^n$n=0..200])[];

%t Select[2^Range[200], IntegerDigits[#][[1]] == 8 &] (* _Amiram Eldar_, Nov 21 2018 *)

%o (GAP) Filtered(List([0..200],n->2^n),i->ListOfDigits(i)[1]=8);

%o (PARI) select(x->(digits(x)[1]==8), vector(200, n, 2^n)) \\ _Michel Marcus_, Nov 21 2018

%Y Cf. A000079 (powers of 2), A008952 (leading digit of 2^n), A217401 (numbers starting with 8).

%Y Powers of 2 with initial digit k, (k = 1..8): A067488, A067480, A320859, A320860, A320861, A320862, A320863, this sequence.

%K base,nonn

%O 1,1

%A _Muniru A Asiru_, Nov 21 2018