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A323758 Lesser of modified exponential amicable pairs. 2
114, 366, 1140, 3660, 3864, 5016, 11040, 16104, 16536, 44772, 57960, 67158, 68640, 142290, 142310, 180960, 196248, 198990, 240312, 248040, 308220, 322080, 326424, 339822, 348840, 352632, 366792, 462330, 669900, 671580, 785148, 815100, 817440, 849240, 912072 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A modified exponential amicable pair (m, n) has A241405(m) = A241405(n) = m + n + 1.

The larger counterparts are in A323759.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..4725 (terms below 2*10^11)

David Moews, Perfect, amicable and sociable numbers.

MATHEMATICA

f[p_, e_] := DivisorSum[e+1, p^(#-1)&]; mesigma[1]=1; mesigma[n_] := Times @@ f @@@FactorInteger@ n; s={}; mes[n_] := mesigma[n]-n; Do[m=mes[n]; If[m>n && mes[m]==n, AppendTo[s, n]], {n, 1, 10000}]; s

PROG

(PARI) f(n) = {my(f=factor(n)); prod(i=1, #f[, 1], sumdiv(f[i, 2]+1, d, f[i, 1]^(d-1))); } \\ A241405

fm(n) = f(n) - n;

isok(n) = my(fn=fm(n)); (fn > n) && (fm(fn) == n); \\ Michel Marcus, Jan 30 2019

CROSSREFS

Cf. A241405, A323757, A323759.

Sequence in context: A300478 A305066 A322541 * A043403 A122279 A251481

Adjacent sequences:  A323755 A323756 A323757 * A323759 A323760 A323761

KEYWORD

nonn

AUTHOR

Amiram Eldar, Jan 26 2019

STATUS

approved

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Last modified June 20 19:36 EDT 2019. Contains 324234 sequences. (Running on oeis4.)