A116955 a(n+1) = a(n) + (if a(n) is odd then (next odd square) else (next even square)), a(0) = 1.

1, 10, 14, 30, 66, 130, 230, 374, 570, 826, 1150, 1550, 2034, 2610, 3286, 4070, 4970, 5994, 7150, 8446, 9890, 11490, 13254, 15190, 17306, 19610, 22110, 24814, 27730, 30866, 34230, 37830, 41674, 45770, 50126, 54750, 59650, 64834, 70310, 76086, 82170, 88570

Offset: 0

Author

Reinhard Zumkeller, Mar 15 2006

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).

Crossrefs

Cf. A002492.

Programs

Maple

A116955:=n->2*(15+n-3*n^2+2*n^3)/3: 1,seq(A116955(n), n=1..60); # Wesley Ivan Hurt, Feb 12 2017

Mathematica

LinearRecurrence[{4,-6,4,-1},{1,10,14,30,66},50] (* Harvey P. Dale, Aug 21 2016 *)

Formula

a(n+1) = A002492(n) + 10.

a(n) = 2*(15+n-3*n^2+2*n^3)/3 for n>0. G.f.: -(9*x^4-30*x^3+20*x^2-6*x-1) / (x-1)^4. - Colin Barker, Jul 18 2013

Extensions

More terms from Colin Barker, Jul 18 2013