

A297837


Solution of the complementary equation a(n) = a(1)*b(n1)  a(0)*b(n2) + 4*n, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.


7



1, 2, 13, 18, 23, 28, 33, 38, 43, 48, 53, 60, 64, 69, 74, 81, 85, 90, 95, 102, 106, 111, 116, 123, 127, 132, 137, 144, 148, 153, 158, 165, 169, 174, 179, 186, 190, 195, 200, 207, 211, 216, 221, 228, 232, 237, 242, 247, 252, 259, 263, 268, 275, 279, 284, 289
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OFFSET

0,2


COMMENTS

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. For a guide to related sequences, see A297830.
Conjecture: a(n)  (3 + sqrt(5))*n < 3 for n >= 1.


LINKS



EXAMPLE

a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, so that a(2) = 13.
Complement: (b(n)) = (3,4,5,6,7,8,9,10,11,12,14,15,16,17,19,20,...)


MATHEMATICA

a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
a[n_] := a[n] = a[1]*b[n  1]  a[0]*b[n  2] + 4 n;
j = 1; While[j < 100, k = a[j]  j  1;
While[k < a[j + 1]  j + 1, b[k] = j + k + 2; k++]; j++]; k
Table[a[n], {n, 0, k}] (* A297836 *)


CROSSREFS



KEYWORD

nonn,easy


AUTHOR



STATUS

approved



