cp's OEIS Frontend

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.

A325352 Heinz number of the differences plus one of the integer partition with Heinz number n.

This page as a plain text file.
%I A325352 #6 Apr 24 2019 19:48:01
%S A325352 1,1,1,2,1,3,1,4,2,5,1,6,1,7,3,8,1,6,1,10,5,11,1,12,2,13,4,14,1,9,1,
%T A325352 16,7,17,3,12,1,19,11,20,1,15,1,22,6,23,1,24,2,10,13,26,1,12,5,28,17,
%U A325352 29,1,18,1,31,10,32,7,21,1,34,19,15,1,24,1,37,6,38
%N A325352 Heinz number of the differences plus one of the integer partition with Heinz number n.
%C A325352 The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
%C A325352 The only fixed point is 1 because otherwise the sequence decreases omega (A001222) by one.
%e A325352 The partition (3,2,2,1) with Heinz number 90 has differences plus one (2,1,2) with Heinz number 18, so a(90) = 18.
%t A325352 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A325352 db[n_]:=Times@@Prime/@(1+Differences[primeMS[n]]);
%t A325352 Table[db[n],{n,100}]
%Y A325352 Positions of m's are A008578 (m = 1), A001248 (m = 2), A006094 (m = 3), A030078 (m = 4), A090076 (m = 5).
%Y A325352 Cf. A007294, A049988, A056239, A093641, A112798, A240026, A320466, A325328, A325351, A325360, A325361, A325368, A325405.
%K A325352 nonn
%O A325352 1,4
%A A325352 _Gus Wiseman_, Apr 23 2019