A074488 a(1)=1, then "jump over next cube": a(n) = 2*(a(n-1)+1)^3-a(n-1).

1, 15, 8177, 1093884103327, 2617845000308809034415180474721383777, 35880772304755070470965980424546414275930627947903988794595699467727630030276033995103117884255220637999070127

Offset

1,2

Comments

The rule "jump over next something" can be varied, see A075694, A075695.

Links

Table of n, a(n) for n=1..6.

Formula

a(1)=1, a(n) = 2*(a(n-1)+1)^3-a(n-1).

Example

a(1)=1; next cube is (a(1)+1)^3=8; "jump over" it: 8+(8-1)=15; a(2)=15; next cube is (a(2)+1)^3=4096; "jump over" it: 4096+(4096-15)=8177.

Maple

a(1) := 1; a(n) := 2*(a(n-1)+1)^2-a(n-1);

Crossrefs

Cf. A075694, A075695.

Sequence in context: A205304 A334835 A206295 * A059950 A198979 A249967

Adjacent sequences: A074485 A074486 A074487 * A074489 A074490 A074491

Keyword

easy,nonn

Author

Zak Seidov, Sep 26 2002

Status

approved