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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.

A347442 Number of factorizations of n with integer reverse-alternating product.

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%I A347442 #13 Oct 22 2023 16:43:32
%S A347442 1,1,1,2,1,1,1,3,2,1,1,3,1,1,1,5,1,3,1,3,1,1,1,3,2,1,3,3,1,1,1,7,1,1,
%T A347442 1,8,1,1,1,3,1,1,1,3,3,1,1,8,2,3,1,3,1,4,1,3,1,1,1,3,1,1,3,11,1,1,1,3,
%U A347442 1,1,1,11,1,1,3,3,1,1,1,8,5,1,1,3,1,1,1,3,1,4,1,3,1,1,1,9,1,3,3,8,1,1,1,3,1,1,1,12
%N A347442 Number of factorizations of n with integer reverse-alternating product.
%C A347442 A factorization of n is a weakly increasing sequence of positive integers > 1 with product n.
%C A347442 We define the alternating product of a sequence (y_1,...,y_k) to be Product_i y_i^((-1)^(i-1)). The reverse-alternating product is the alternating product of the reversed sequence.
%H A347442 Antti Karttunen, <a href="/A347442/b347442.txt">Table of n, a(n) for n = 1..65537</a>
%F A347442 a(2^n) = A000041(n).
%e A347442 The a(n) factorizations for n = 4, 8, 16, 32, 36, 54, 64:
%e A347442   (4)    (8)      (16)       (32)         (36)       (54)     (64)
%e A347442   (2*2)  (2*4)    (2*8)      (4*8)        (6*6)      (3*18)   (8*8)
%e A347442          (2*2*2)  (4*4)      (2*16)       (2*18)     (2*3*9)  (2*32)
%e A347442                   (2*2*4)    (2*2*8)      (3*12)     (3*3*6)  (4*16)
%e A347442                   (2*2*2*2)  (2*4*4)      (2*2*9)             (2*4*8)
%e A347442                              (2*2*2*4)    (2*3*6)             (4*4*4)
%e A347442                              (2*2*2*2*2)  (3*3*4)             (2*2*16)
%e A347442                                           (2*2*3*3)           (2*2*2*8)
%e A347442                                                               (2*2*4*4)
%e A347442                                                               (2*2*2*2*4)
%e A347442                                                               (2*2*2*2*2*2)
%t A347442 facs[n_]:=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&,Select[facs[n/d],Min@@#>=d&]],{d,Rest[Divisors[n]]}]];
%t A347442 revaltprod[q_]:=Product[Reverse[q][[i]]^(-1)^(i-1),{i,Length[q]}];
%t A347442 Table[Length[Select[facs[n],IntegerQ@*revaltprod]],{n,100}]
%o A347442 (PARI) A347442(n, m=n, ap=1, e=0) = if(1==n, 1==denominator(ap), sumdiv(n, d, if((d>1)&&(d<=m), A347442(n/d, d, ap * d^((-1)^e), 1-e)))); \\ _Antti Karttunen_, Oct 22 2023
%Y A347442 The restriction to powers of 2 is A000041, reverse A344607.
%Y A347442 Positions of 2's are A001248.
%Y A347442 Positions of 1's are A005117.
%Y A347442 Positions of non-1's are A013929.
%Y A347442 Allowing any alternating product <= 1 gives A339846.
%Y A347442 Allowing any alternating product > 1 gives A339890.
%Y A347442 The non-reverse version is A347437.
%Y A347442 The reciprocal version is A347438.
%Y A347442 The even-length case is A347439.
%Y A347442 Allowing any alternating product < 1 gives A347440.
%Y A347442 The odd-length case is A347441, ranked by A347453.
%Y A347442 The additive version is A347445, ranked by A347457.
%Y A347442 The non-reverse additive version is A347446, ranked by A347454.
%Y A347442 Allowing any alternating product >= 1 gives A347456.
%Y A347442 The ordered version is A347463.
%Y A347442 A038548 counts possible reverse-alternating products of factorizations.
%Y A347442 A071321 gives the alternating sum of prime factors (reverse: A071322).
%Y A347442 A236913 counts partitions of 2n with reverse-alternating sum <= 0.
%Y A347442 A273013 counts ordered factorizations of n^2 with alternating product 1.
%Y A347442 Cf. A000290, A025047, A330972, A347443, A347449, A347451, A347458, A347459, A347460, A347462.
%K A347442 nonn
%O A347442 1,4
%A A347442 _Gus Wiseman_, Sep 08 2021
%E A347442 Data section extended up to a(108) by _Antti Karttunen_, Oct 22 2023