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A344470 Record values in A002654. 2
1, 2, 3, 4, 6, 8, 9, 12, 16, 18, 20, 24, 32, 36, 40, 48, 64, 72, 80, 96, 128, 144, 160, 192, 216, 256, 288, 320, 384, 432, 512, 576, 640, 768, 864, 960, 1024, 1152, 1280, 1536, 1728, 1920, 2048, 2304, 2560, 2880, 3072, 3456, 3840, 4096, 4608, 5120, 5760, 6144 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also numbers k such that A018782(m) > A018782(k) for all m > k.

LINKS

Jianing Song, Table of n, a(n) for n = 1..424

FORMULA

a(n) = A071385(n+1)/4.

a(n) = A000005(A071383(n+1)) = A002654(A071383(n+1)).

EXAMPLE

9 is a term because the circle with radius sqrt(4225) centered at the origin hits exactly 4*9 = 36 integer points, and any circle with radius < sqrt(4225) centered at the origin hits fewer than 36 points.

PROG

(PARI) my(v=list(10^15), rec=0); for(n=1, #v, if(numdiv(v[n])>rec, rec=numdiv(v[n]); print1(rec, ", "))) \\ see program for A054994

CROSSREFS

Cf. A071383, A071385, A002654, A018782, A000005, A054994.

Records of Sum_{d|n} kronecker(m, d): A344472 (m=-3), this sequence (m=-4), A279542 (m=-6).

Sequence in context: A067947 A279542 A053640 * A296991 A097755 A301704

Adjacent sequences:  A344467 A344468 A344469 * A344471 A344472 A344473

KEYWORD

nonn

AUTHOR

Jianing Song, May 20 2021

STATUS

approved

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Last modified August 5 11:15 EDT 2021. Contains 346467 sequences. (Running on oeis4.)