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 A102383 #12 Oct 02 2024 09:18:44 %S A102383 0,1,2,3,1,1,2,1,3,2,1,2,4,2,2,3,3,1,4,4,4,4,4,3,1,4,7,5,2,2,2,4,4,3, %T A102383 2,2,3,1,4,5,4,6,3,4,4,1,4,2,4,4,3,3,3,4,2,1,3,3,4,7,6,4,5,4,4,2,3,5, %U A102383 7,3,1,9,4,3,4,6,4,1,4,4,4,5,6,4,3,2,2,3,3,5,6,3,4,4,3,4,4,4,3,12,3,6,5,3,5 %N A102383 a(n) = A001222(A004094(n)). %e A102383 n = 26: reverse(2^26) = 46880176 = 2^4*7*641*653, so a(26) = 7. %e A102383 n = 38: reverse(2^38) = 449609778472 = 2^3*56201222309, so a(38) = 4. - _Sean A. Irvine_, Sep 26 2023 %t A102383 a[n_] := PrimeOmega[IntegerReverse[2^n]]; Array[a, 100, 0] (* _Amiram Eldar_, Oct 02 2024 *) %o A102383 (PARI) a(n) = bigomega(fromdigits(Vecrev(digits(2^n)))); \\ _Amiram Eldar_, Oct 02 2024 %Y A102383 Cf. A001222, A004094, A102382, A102384, A102385. %K A102383 nonn,base %O A102383 0,3 %A A102383 _Reinhard Zumkeller_, Jan 06 2005 %E A102383 a(38) corrected by _Sean A. Irvine_, Sep 26 2023