A111104 Difference between successive terms of A051484.

2, 1, 4, 6, 6, 6, 18, 18, 48, 30, 12, 30, 6, 42, 66, 42, 150, 18, 12, 48, 6, 72, 12, 30, 138, 60, 18, 84, 204, 54, 36, 6, 144, 12, 156, 24, 18, 60, 36, 6, 126, 48, 18, 168, 42, 12, 12, 204, 78, 6, 6, 18, 54, 84, 30, 24, 18, 150, 72, 6, 6, 36, 42, 66, 126, 318, 186, 18, 24, 54

Offset: 1

Author

Walter Kehowski, Oct 14 2005

Keywords

• nonn

Comments

All elements of A051484 from the fourth element, 7, onward are either 1 or 7 modulo 12. Each difference between successive terms of A051484 from the fourth term, 7, onward are equal to 0 or 6 modulo 12.

Examples

			a(8)=A051484(8)-A051484(7)=43-25=18.
		

Crossrefs

Cf. A051484.

Programs

Maple

M:=[0,2]: isElement := proc(n) global M; local b, j, k; b:=true; for j from 1 to nops(M)-1 do for k from j+1 to nops(M) do if M[j] = n mod M[k] then b:=false; break; fi od od; return b end: for z to 1 do for n from 3 to 1000 do if isElement(n) then M:=[op(M),n] fi od od; M; map(proc(k) M[k]-M[k-1] end, [$2..nops(M)]);

Mathematica

a[1] = 0; a[2] = 2; a[n_] := a[n] = Block[{k = a[n - 1] + 1, t = a[ # ] & /@ Range[n - 1]}, While[ Intersection[t, Union[ Mod[k, Rest[ t]]]] != {}, k++ ]; k]; t = Table[ a[n], {n, 71}]; Drop[t, 1] - Drop[t, -1] (* Robert G. Wilson v *)

Formula

a(n) = A051484(n+1)-A051484(n), n>=1.

Extensions

More terms from Robert G. Wilson v, Oct 19 2005