This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A379032 #8 Dec 16 2024 02:16:05 %S A379032 14,44,957,1334,1485,1634,1652,2204,2685,3195,3451,3956,4136,5547, %T A379032 8495,8636,8907,9844,11515,12256,14876,15608,19491,20145,20155,27519, %U A379032 27643,33998,35235,36575,38180,41265,41547,42818,45716,48364,74918,79316,79826,79833,84134 %N A379032 Numbers k such that k and k+1 have an equal sum of modified exponential divisors: A241405(k) = A241405(k+1). %H A379032 Amiram Eldar, <a href="/A379032/b379032.txt">Table of n, a(n) for n = 1..1918</a> (terms below 10^10) %t A379032 f[p_, e_] := DivisorSum[e + 1, p^(# - 1) &]; mesigma[1] = 1; mesigma[n_] := mesigma[n] = Times @@ f @@@ FactorInteger[n]; Select[Range[10^5], mesigma[#] == mesigma[#+1] &] %o A379032 (PARI) mesigma(n) = {my(f=factor(n)); prod(i=1, #f~, sumdiv(f[i, 2]+1, d, f[i, 1]^(d-1))); } %o A379032 lista(kmax) = {my(m1 = 1, m2); for(k = 2, kmax, m2 = mesigma(k); if(m1 == m2, print1(k-1, ", ")); m1 = m2);} %Y A379032 Cf. A241405. %Y A379032 Similar sequences: A002961, A064115, A064125, A293183, A306985. %K A379032 nonn %O A379032 1,1 %A A379032 _Amiram Eldar_, Dec 14 2024