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 A085491 Number of ways to write n as sum of distinct divisors of n+1. 5
 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 2, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 5, 0, 0, 0, 1, 0, 3, 0, 1, 0, 0, 0, 5, 0, 0, 0, 3, 0, 2, 0, 0, 0, 0, 0, 10, 0, 0, 0, 0, 0, 1, 0, 2, 0, 0, 0, 31, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 26, 0, 0, 0, 0, 0, 1, 0, 6, 0, 0, 0, 23, 0, 0, 0, 1, 0, 20, 0, 0, 0, 0, 0, 21, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,12 COMMENTS a(A085492(n)) = 0; a(A085493(n)) > 0; a(A085494(n)) = 1. LINKS Alois P. Heinz, Table of n, a(n) for n = 0..10000 EXAMPLE n=11, divisors of 12=11+1 that are not greater 11: {1,2,3,4,6}, 11=6+5=6+4+1, therefore a(11)=2. MAPLE a:= proc(m) option remember; local b, l; b, l:=       proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,         b(n, i-1)+`if`(l[i]>n, 0, b(n-l[i], i-1))))       end, sort([numtheory[divisors](m+1)[]]);       forget(b); b(m, nops(l)-1)     end: seq(a(n), n=0..120);  # Alois P. Heinz, Mar 12 2019 MATHEMATICA a[n_] := Module[{dd}, dd = Select[Divisors[n+1], # <= n&]; Select[ IntegerPartitions[n, dd // Length, dd], Reverse[#] == Union[#]&] // Length]; Array[a, 100, 0] (* Jean-François Alcover, Mar 12 2019 *) CROSSREFS Cf. A085496. Sequence in context: A280751 A280749 A321936 * A321013 A284258 A322389 Adjacent sequences:  A085488 A085489 A085490 * A085492 A085493 A085494 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jul 03 2003 EXTENSIONS a(0)=1 prepended by Alois P. Heinz, Mar 12 2019 STATUS approved

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Last modified December 12 22:06 EST 2019. Contains 329963 sequences. (Running on oeis4.)