A284124 Remainder when 4*n is divided by A005185(n).

0, 0, 0, 1, 2, 0, 3, 2, 0, 4, 2, 0, 4, 0, 0, 1, 8, 6, 10, 8, 0, 4, 8, 0, 2, 6, 12, 0, 4, 8, 4, 9, 13, 16, 14, 11, 8, 20, 9, 6, 3, 7, 4, 8, 12, 16, 20, 0, 4, 0, 24, 12, 4, 6, 10, 0, 4, 22, 12, 16, 20, 24, 12, 25, 12, 36, 23, 8, 3, 0, 25, 22, 12, 23, 20, 31, 14, 32, 29, 19, 16

Offset: 1

Author

Altug Alkan, Mar 20 2017

Keywords

• nonn
• look

Examples

			a(5) = 2 because remainder when 4*5 = 20 is divided by A005185(5) = 3 is 2.
		

Links

• Altug Alkan, Table of n, a(n) for n = 1..10000
• Altug Alkan, Alternative Scatterplot of A284124

Crossrefs

Cf. A005185, A008586.

Programs

Mathematica

a[1] = a[2] = 1; a[n_] := a[n] = a[n - a[n - 1]] + a[n - a[n - 2]]; Table[Mod[4 n, a@ n], {n, 81}] (* Michael De Vlieger, Mar 20 2017 *)

PARI

a=vector(1000); a[1]=a[2]=1; for(n=3, #a, a[n]=a[n-a[n-1]]+a[n-a[n-2]]); vector(1000, n, (4*n)%a[n])

Formula

a(n) = A008586(n) mod A005185(n) for n > 0.