cp's OEIS Frontend

A337055 Numbers that are k+A000010(k) for at least two different k.

%I A337055 #8 Aug 14 2020 01:33:26
%S A337055 24,32,33,38,45,48,56,64,76,86,93,96,112,113,128,140,150,152,153,172,
%T A337055 182,192,200,203,213,216,224,225,231,256,258,263,280,293,297,300,304,
%U A337055 320,325,326,333,342,344,345,352,364,374,380,383,384,393,397,400,402,410,413,429,432,448,459,470,473
%N A337055 Numbers that are k+A000010(k) for at least two different k.
%C A337055 If p>2 and 4*p-1 are prime, then 12*p-4 is in the sequence.
%C A337055 If p>3 and (5*p-1)/2 are prime, then 5*p-2 is in the sequence.
%H A337055 Robert Israel, <a href="/A337055/b337055.txt">Table of n, a(n) for n = 1..10000</a>
%e A337055 a(3)=33 is in the sequence because 33 = 17 + A000010(17) = 21 + A000010(21).
%p A337055 N:= 20000: # for terms <= N
%p A337055 V:= Vector(N):
%p A337055 for n from 1 to N do
%p A337055   v:= n + numtheory:-phi(n);
%p A337055   if v <= N then V[v]:= V[v]+1 fi
%p A337055 od:
%p A337055 select(t -> V[t]>=2, [$1..N]);
%Y A337055 Cf. A000010, A062737.
%K A337055 nonn
%O A337055 1,1
%A A337055 _J. M. Bergot_ and _Robert Israel_, Aug 12 2020