A109070 Number of digits in numbers appearing in A108225.

1, 1, 1, 1, 2, 2, 4, 7, 13, 25, 50, 99, 196, 392, 783, 1566, 3131, 6261, 12521, 25042, 50084, 100166, 200332, 400663, 801325, 1602649, 3205298, 6410595, 12821190, 25642379, 51284758

Offset: 0

Author

Zak Seidov, Jun 18 2005

Keywords

• base
• nonn

Comments

Starting with a(14)=783, a(n) = 2*a(n-1) - (1 or 0).

Examples

			A109070(10)=50 because A108225(10)=16217557574922386301420536972254869595782763547562 has 50 digits.
		

Crossrefs

Cf. A108225.

Programs

Mathematica

nxt[{a_,b_}]:={b,((a+b)(b-a+1))/2}; Join[{1},IntegerLength/@ Transpose[ NestList[nxt,{0,2},31]][[2]]] (* Harvey P. Dale, Feb 14 2012 *)