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A172468 Numbers such that A166986(n)/2-A167389(n) = 1. 1
50, 59, 111, 120, 181, 242, 251, 303, 312, 373, 434, 495, 504, 556, 565, 626, 687, 696, 748, 757, 818, 879, 940, 949, 1001, 1010, 1071, 1132, 1141, 1193, 1202, 1254, 1263, 1324, 1385, 1394, 1446, 1455, 1516, 1577, 1638, 1647, 1699, 1708, 1769, 1830, 1839 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It is conjectured that the successive differences of this sequence, A172470, are limited to three numbers: 9, 52 and 61 where it is noted that 61-52 = 9, (52+2)/9 = 6, (61+2)/9 = 7 and we have lcm(9,52,61) = 28548 = 13^4 - 13 and 6+7=13

LINKS

Table of n, a(n) for n=1..47.

Stephen Crowley, A Mysterious Three Term Integer Sequence Related to a Lambert W Function Solution to a Certain Transcendental Equation

MAPLE

[ListTools[SearchAll](1, [seq(round(evalf(floor((n+2)/ln(2))-2-(argument(exp(-(ln(2)+LambertW(n, -ln(sqrt(2))))/ln(2)))*ln(2)+Im(LambertW(n, -ln(sqrt(2)))))/(2*Pi*ln(2)))), n = 1 .. 10000)])]

CROSSREFS

Cf. A166986, A167389.

Sequence in context: A114504 A227548 A282112 * A046832 A046834 A046836

Adjacent sequences:  A172465 A172466 A172467 * A172469 A172470 A172471

KEYWORD

hard,nonn

AUTHOR

Stephen Crowley, Feb 03 2010

STATUS

approved

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Last modified November 14 07:29 EST 2019. Contains 329111 sequences. (Running on oeis4.)