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A136477 Numbers x such that for some y < sqrt(2x), x^2 + x + y^2 is an odd primitive abundant number, A136476(n). 3
97, 112, 122, 135, 144, 179, 202, 207, 214, 217, 227, 354, 359, 477, 507, 569, 612, 632, 639, 732, 832, 2124, 2359, 2362, 2440, 2466, 2517, 2970, 3097, 3247, 3342, 3367, 3374, 3419, 3425, 3518, 3545, 3562, 3644, 3672, 3699, 3789, 3879, 3969, 3985, 4050 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The corresponding y-values are listed in A136478. (Unlike the x-values listed here, y is not increasing with A136476(n).)

LINKS

Table of n, a(n) for n=1..46.

EXAMPLE

97^2 + 97 + 7^2 = 9555 = A136476(1) is an odd primitive abundant number, so a(1) = 97.

PROG

(PARI) is(x, n=x^2+x+1, f)={forstep(y=1, sqrtint(2*x), 2, sigma(n+=y*4-4, -1)>2 || next; for(i=1, #f=factor(n)[, 1], sigma(n\f[i], -1)>2 && next(2)); return(1))} \\ M. F. Hasler, Feb 22 2017

CROSSREFS

Cf. A006038, A136476, A136478, A136479.

Sequence in context: A039490 A033202 A160032 * A078494 A139980 A140830

Adjacent sequences:  A136474 A136475 A136476 * A136478 A136479 A136480

KEYWORD

nonn

AUTHOR

Pierre CAMI, Dec 31 2007

EXTENSIONS

Edited by M. F. Hasler, Feb 22 2017

STATUS

approved

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Last modified August 22 03:28 EDT 2017. Contains 290942 sequences.