A071584 Powers of 7 written backwards.

1, 7, 94, 343, 1042, 70861, 946711, 345328, 1084675, 70635304, 942574282, 3476237791, 10278214831, 70401098869, 948270322876, 3499051657474, 10696503923233, 702789315036232, 9440197953148261, 34137358159889311

Offset: 0

Author

Benoit Cloitre, Jun 01 2002

Keywords

• easy
• nonn
• base

Links

• Alois P. Heinz, Table of n, a(n) for n = 0..1000

Programs

Maple

a:= n-> (s-> parse(cat(s[-i]$i=1..length(s))))(""||(7^n)):
seq(a(n), n=0..50);  # Alois P. Heinz, Apr 09 2015

Mathematica

FromDigits[Reverse[IntegerDigits[#]]]&/@(7^Range[0,20]) (* Harvey P. Dale, Apr 29 2012 *)
IntegerReverse[7^Range[0,20]] (* Harvey P. Dale, Jul 06 2025 *)

PARI

for(i=1,50,n=5^i; s=ceil(log(n)/log(10)); print1(sum(i=0,s,10^(s-i-1)*(floor(n/10^i)-10*floor(n/10^(i+1)))),","))