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.

A325097 Heinz numbers of integer partitions whose distinct parts have no binary carries.

This page as a plain text file.
%I A325097 #7 Jul 27 2019 14:57:51
%S A325097 1,2,3,4,5,6,7,8,9,11,12,13,14,16,17,18,19,21,23,24,25,26,27,28,29,31,
%T A325097 32,33,35,36,37,38,41,42,43,47,48,49,52,53,54,56,57,58,59,61,63,64,67,
%U A325097 69,71,72,73,74,76,79,81,83,84,86,89,95,96,97,98,99,101
%N A325097 Heinz numbers of integer partitions whose distinct parts have no binary carries.
%C A325097 A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion.
%C A325097 The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1) * ... * prime(y_k), so these are numbers whose distinct prime indices have no binary carries.
%e A325097 Most small numbers are in the sequence, however the sequence of non-terms together with their prime indices begins:
%e A325097   10: {1,3}
%e A325097   15: {2,3}
%e A325097   20: {1,1,3}
%e A325097   22: {1,5}
%e A325097   30: {1,2,3}
%e A325097   34: {1,7}
%e A325097   39: {2,6}
%e A325097   40: {1,1,1,3}
%e A325097   44: {1,1,5}
%e A325097   45: {2,2,3}
%e A325097   46: {1,9}
%e A325097   50: {1,3,3}
%e A325097   51: {2,7}
%e A325097   55: {3,5}
%e A325097   60: {1,1,2,3}
%e A325097   62: {1,11}
%e A325097   65: {3,6}
%e A325097   66: {1,2,5}
%e A325097   68: {1,1,7}
%e A325097   70: {1,3,4}
%t A325097 binpos[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
%t A325097 stableQ[u_,Q_]:=!Apply[Or,Outer[#1=!=#2&&Q[#1,#2]&,u,u,1],{0,1}];
%t A325097 Select[Range[100],stableQ[PrimePi/@First/@FactorInteger[#],Intersection[binpos[#1],binpos[#2]]!={}&]&]
%Y A325097 Cf. A000110, A000720, A001222, A050315, A056239, A080572, A112798, A247935.
%Y A325097 Cf. A325094, A325095, A325096, A325097, A325098, A325100, A325102, A325103.
%K A325097 nonn
%O A325097 1,2
%A A325097 _Gus Wiseman_, Mar 27 2019