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A063072 Sum of divisors of Ramanujan's highly composite numbers, or sigma(A002182(n)). 4
1, 3, 7, 12, 28, 60, 91, 124, 168, 360, 546, 744, 1170, 2418, 2880, 4368, 5952, 9360, 19344, 28800, 39312, 59520, 79248, 99944, 112320, 180048, 203112, 232128, 345600, 471744, 714240, 950976, 1199328, 1451520, 2160576, 2437344, 2926080 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..50 from Harry J. Smith)

FORMULA

a(n) = A000203(A002182(n)). - Michel Marcus, Jun 28 2018

MATHEMATICA

s={}; dm=0; Do[d = DivisorSigma[0, n]; If[d > dm, dm=d; AppendTo[s, DivisorSigma[1, n]]], {n, 1, 10^5}]; s (* Amiram Eldar, Jun 28 2019 *)

PROG

(PARI) a=0; j=[]; for(n=1, 200000, b=numdiv(n); if(b>a, a=b; j=concat(j, sigma(n)))); j

(PARI) { n=a=0; for (m=1, 10^9, b=numdiv(m); if(b>a, a=b; write("b063072.txt", n++, " ", sigma(m)); if (n==50, break)) ) } \\ Harry J. Smith, Aug 16 2009

CROSSREFS

Cf. A000005, A004394, A002182, A002183, A002473, A000203.

Sequence in context: A196917 A256259 A182941 * A007626 A193297 A240738

Adjacent sequences:  A063069 A063070 A063071 * A063073 A063074 A063075

KEYWORD

easy,nonn

AUTHOR

Jason Earls, Aug 02 2001

EXTENSIONS

More terms from Reiner Martin (reinermartin(AT)hotmail.com), Dec 22 2001

STATUS

approved

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Last modified February 28 08:44 EST 2020. Contains 332323 sequences. (Running on oeis4.)