A111363 - OEIS

A111363

a(n) = A108783(n) + 1.

1, 3, 7, 11, 13, 27, 31, 33, 37, 51, 53, 57, 61, 63, 127, 131, 133, 137, 151, 153, 161, 165, 167, 171, 173, 175, 177, 181, 185, 193, 195, 199, 201, 203, 215, 217, 221, 227, 229, 231, 235, 237, 241, 243, 245, 261, 263, 265, 273, 275, 279, 283, 287, 289, 291, 295

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OFFSET

1,2

COMMENTS

Positions of the 1's in A083952 but indexing that sequence starting at 1. A108783 is the preferred version.

LINKS

Table of n, a(n) for n=1..56.

FORMULA

It appears that a(n)~4.1*n.

MATHEMATICA

a[0] = 1; a[l_] := a[l] = Block[{k = 1, s = Sum[ a[i]*x^i, {i, 0, l - 1}]}, While[ IntegerQ[ Last[ CoefficientList[ Series[(s + k*x^l)^(1/2), {x, 0, l}], x]]] != True, k++ ]; k]; Position[ Table[a[n], {n, 0, 300}], 1] // Flatten

CROSSREFS

Cf. A083952. See A108783 for another version.

Sequence in context: A225222 A106561 A296929 * A193258 A114273 A173295

Adjacent sequences: A111360 A111361 A111362 * A111364 A111365 A111366

KEYWORD

nonn

AUTHOR

Paul D. Hanna and Robert G. Wilson v, Nov 08 2005

STATUS

approved