The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A302934 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A302934

Highly composite deficient numbers: deficient numbers k whose number of divisors d(k) > d(m) for all deficient numbers m < k.
(history; published version)

#12 by Jon E. Schoenfield at Wed Jul 21 00:44:24 EDT 2021

STATUS

reviewed

approved

#11 by Michel Marcus at Wed Jul 21 00:05:41 EDT 2021

STATUS

proposed

reviewed

#10 by Jon E. Schoenfield at Wed Jul 21 00:04:39 EDT 2021

STATUS

editing

proposed

#9 by Jon E. Schoenfield at Wed Jul 21 00:04:37 EDT 2021

NAME

Highly composite deficient numbers: deficient numbers n such that their k whose number of divisors d(nk) > d(m) for all deficient numbers m < nk.

STATUS

approved

editing

#8 by Michel Marcus at Sun Apr 22 05:18:57 EDT 2018

STATUS

reviewed

approved

#7 by Joerg Arndt at Sun Apr 22 05:12:52 EDT 2018

STATUS

proposed

reviewed

#6 by Michel Marcus at Tue Apr 17 11:43:20 EDT 2018

STATUS

editing

proposed

#5 by Michel Marcus at Tue Apr 17 11:43:17 EDT 2018

PROG

(PARI) lista(nn) = {my(maxd = 0); for (n=1, nn, if ((sigma(n) < 2*n) && (numdiv(n) > maxd), maxd = numdiv(n); print1(n, ", "); ); ); } \\ Michel Marcus, Apr 17 2018

STATUS

proposed

editing

#4 by Amiram Eldar at Mon Apr 16 05:18:16 EDT 2018

STATUS

editing

proposed

#3 by Amiram Eldar at Mon Apr 16 05:10:09 EDT 2018

NAME

allocated Highly composite deficient numbers: deficient numbers n such that their number of divisors d(n) > d(m) for Amiram Eldarall deficient numbers m < n.

DATA

1, 2, 4, 8, 16, 32, 64, 105, 225, 315, 1155, 2475, 4455, 8775, 26325, 27027, 63063, 106029, 247401, 693693, 829521, 969969, 2241603, 3741309, 7894341, 8083075, 32569173, 33671781, 37182145, 56581525, 146791359, 185910725, 622396775, 929553625, 1301375075

OFFSET

1,2

COMMENTS

The record numbers of divisors are 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 16, 18, 20, 24, 30, 32, 36, 40, 48, 54, 60, 64, 72, 80, 84, 96, 108, 112, 128, 144, 160, 192, 216, 256, 288, ...

MATHEMATICA

a={}; dm=0; Do[ If[DivisorSigma[1, n]>=2n, Continue[]]; d=DivisorSigma[0, n]; If[d>dm, dm=d; AppendTo[a, n]], {n, 1, 1000000}]; a

CROSSREFS

Cf. A000005, A002182, A005100.

KEYWORD

allocated

nonn

AUTHOR

Amiram Eldar, Apr 16 2018

STATUS

approved

editing