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A116955
a(n+1) = a(n) + (if a(n) is odd then (next odd square) else (next even square)), a(0) = 1.
4
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
0,2
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
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 *)
CROSSREFS
Cf. A002492.
Sequence in context: A115391 A241162 A164765 * A192291 A144967 A328635
KEYWORD
nonn,easy
AUTHOR
Reinhard Zumkeller, Mar 15 2006
EXTENSIONS
More terms from Colin Barker, Jul 18 2013
STATUS
approved