A132114 Multiply previous term by 7 and reverse.

1, 7, 94, 856, 2995, 56902, 413893, 1527982, 47859601, 702710533, 1373798194, 8537856169, 38139946795, 565726979662, 4367588800693, 15840612137503, 125269482488011, 770614773688678, 6470285143034935, 54544210069919254

Offset: 1

Author

Rachit Agrawal (rachit_agrawal(AT)daiict.ac.in), Oct 31 2007

Keywords

• base
• nonn

Examples

			a(4) = reverse(7 * a(3)) = reverse(7 * reverse(7 * a(2))) = reverse(7 * reverse(7 * reverse(7 * a(1)))) = reverse(7 * reverse(7 * reverse(7))) = reverse(7*94) = 856.
		

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 1..1000
• Vaclav Kotesovec, Plot of a(n)^(1/n) for n = 1..10000

Crossrefs

Cf. A036447 (*2), A163632 (*3), A132064 (*4), A045539 (*5), A132078 (*6), A132113 (*8), A133361 (*9).

Programs

Magma

f:=func; a:=[1]; for n in [2..20] do Append(~a,f(a[n-1]));  end for; a; // Marius A. Burtea, Jan 03 2020

PARI

seq(n)={my(a=vector(n)); a[1]=1; for(n=2, #a, a[n]=fromdigits(Vecrev(digits(a[n-1]*7)))); a} \\ Andrew Howroyd, Jan 02 2020

Formula

a(n) = reverse(7 * a(n-1)) with a(1) = 1.

Extensions

Name edited by Andrew Howroyd, Jan 02 2020