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 A329603 #38 Mar 12 2023 04:16:07 %S A329603 2,5,8,15,18,11,50,45,20,125,98,33,242,245,32,135,338,77,578,375,72, %T A329603 605,722,99,42,845,60,735,1058,17,1682,405,200,1445,162,231,1922,1805, %U A329603 392,1125,2738,1331,3362,1815,44,2645,3698,297,110,275,968,2535,4418,539,450,2205,1352,4205,5618,51,6962,4805,500,1215,882,1859,7442,4335,2312 %N A329603 a(n) = A005940(1+(1+(3*A156552(n)))) = (1/2) * A005940(1+(3*A156552(2*n))). %C A329603 Function n -> 3n+1 (A016777) conjugated by A156552. - _Antti Karttunen_, Aug 21 2021 %H A329603 Antti Karttunen, <a href="/A329603/b329603.txt">Table of n, a(n) for n = 1..16384</a> %H A329603 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a> %F A329603 a(n) = (1/2) * A005940(1+(3*A156552(2*n))). %F A329603 From _Antti Karttunen_, Feb 14 2021: (Start) %F A329603 A156552(2*a(n)) = 3*A156552(2*n) = 3*(1+2*A156552(n)) = 3 + 6*A156552(n). %F A329603 a(n) = A341510(n,2n) = A005940(1+A156552(n)+A156552(2n)) = A005940(1+(1+(3*A156552(n)))). %F A329603 a(n) = A005940(1+A016777(A156552(n))). %F A329603 For all n >= 1, A329903(a(n)) = A332814(a(n)) = A332823(A332461(a(n))) = 1. %F A329603 For all n >= 1, A341354(a(n)) > 0. %F A329603 For all n >= 1, A000035(a(n)) = 1 - A000035(n). [Flips the parity of n] %F A329603 (End) %F A329603 a(n) = A332449(2*n)/2, a(n) = Sum_{d|n} A347117(d). - _Antti Karttunen_, Aug 21 2021 %o A329603 (PARI) %o A329603 A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; %o A329603 A156552(n) = { my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res }; %o A329603 A329603(n) = ((1/2)*A005940(1+(3*A156552(2*n)))); %o A329603 (Python) %o A329603 from math import prod %o A329603 from itertools import accumulate %o A329603 from collections import Counter %o A329603 from sympy import prime, primepi, factorint %o A329603 def A329603(n): return prod(prime(len(a)+1)**b for a, b in Counter(accumulate(bin(1+3*sum((1<<primepi(p)-1)<<i for i, p in enumerate(factorint(n,multiple=True))))[2:].split('1')[:0:-1])).items()) # _Chai Wah Wu_, Mar 11 2023 %Y A329603 Permutation of A329604. %Y A329603 Cf. A000035, A005940, A016777, A064989, A156552, A329903, A332449, A332461, A332814, A332823, A341354, A341510, A341515, A341516, A347117 (Möbius transform). %Y A329603 A skewed diagonal of A341510. %K A329603 nonn %O A329603 1,1 %A A329603 _Antti Karttunen_, Nov 21 2019 %E A329603 New primary definition added by _Antti Karttunen_, Feb 14 2021