A074140 Sum of least integers of prime signatures over all partitions of n.
1, 2, 10, 50, 346, 3182, 38770, 609290, 11226106, 250148582, 7057182250, 216512001950, 7903965900226, 321552174623162, 13779150603234010, 644574260638821590, 33968684108427733426, 1994885097404292104942, 121496572792097514728530, 8114030083731371137603190
Offset: 0
Keywords
Examples
a(6) = 64+96+144+216+240+360+900+840+1260+4620+30030 = 38770.
Links
- Peter Luschny and Alois P. Heinz, Table of n, a(n) for n = 0..350
- Eric Weisstein's World of Mathematics, Prime Signature
- Wikipedia, Partition (number theory)
- Wikipedia, Prime signature
- Index entries for sequences related to prime signature
Programs
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Maple
b:= proc(n, i, j) option remember; `if`(n=0, 1, `if`(i<1, 0, b(n, i-1, j)+ `if`(i>n, 0, ithprime(j)^i*b(n-i, i, j+1)))) end: a:= n-> b(n$2, 1): seq(a(n), n=0..40); # Alois P. Heinz, Aug 03 2013
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Mathematica
b[n_, i_, j_] := b[n, i, j] = If[n == 0, 1, If[i<1, 0, b[n, i-1, j]+If[i>n, 0, Prime[j]^i*b[n-i, i, j+1]]]]; a[n_] := b[n, n, 1]; Table[a[n], {n, 0, 20}] (* Jean-François Alcover, Feb 25 2014, after Alois P. Heinz *)
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Sage
def A074140(n): L = [] P = primes_first_n(n) for p in Partitions(n): m = mul(P[i]^pi for i, pi in enumerate(p)) L.append(m) return add(L) [A074140(n) for n in (0..20)] # Peter Luschny, Aug 02 2013
Extensions
More terms from Alford Arnold, Sep 10 2002
a(10)-a(12) from Thomas A. Rockwell (LlewkcoRAT(AT)aol.com), Sep 30 2004
a(12) corrected by Peter Luschny, Aug 03 2013
New name from Alois P. Heinz, Aug 03 2013
Comments