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A323759 Larger of modified exponential amicable pairs. 2
126, 378, 1260, 3780, 4584, 5544, 11424, 16632, 16728, 49308, 68760, 73962, 88608, 179118, 168730, 212160, 225096, 256338, 266568, 250920, 365700, 374304, 391656, 374418, 387720, 386568, 393528, 548550, 827700, 739620, 827652, 932100, 912288, 935400, 1052088 (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 lesser counterparts are in A323758.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..4725 (terms whose lesser counterparts 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, m]], {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 > 0) && (fn < n) && (fm(fn) == n); \\ Michel Marcus, Jan 30 2019

CROSSREFS

Cf. A241405, A323757, A323758.

Sequence in context: A181262 A181255 A322542 * A102805 A267556 A268119

Adjacent sequences:  A323756 A323757 A323758 * A323760 A323761 A323762

KEYWORD

nonn

AUTHOR

Amiram Eldar, Jan 26 2019

STATUS

approved

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Last modified May 26 19:44 EDT 2019. Contains 323597 sequences. (Running on oeis4.)