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A381585 Starts of runs of 5 consecutive integers that are all terms in A381581.

%I A381585 #18 Mar 03 2025 13:27:39
%S A381585 57744971,159104411,203738652,212548572,260463851,361823291,413644572,
%T A381585 431577521,440353328,520800012,717222337,726300972,779825648,
%U A381585 843559091,913313321,945016812,986681527,1091786528,1116032201,1185786431,1318751081,1347208812,1360423692,1418212627
%N A381585 Starts of runs of 5 consecutive integers that are all terms in A381581.
%C A381585 Are there 6 consecutive integers that are all terms in A381581?
%H A381585 Amiram Eldar, <a href="/A381585/b381585.txt">Table of n, a(n) for n = 1..130</a>
%e A381585 57744971 is a term since A291711(57744971) = 17 divides 57744971, A291711(57744972) = 18 divides 57744972, A291711(57744973) = 13 divides 57744973, A291711(57744974) = 14 divides 57744974, and A291711(57744975) = 15 divides 57744975.
%o A381585 (PARI) mx = 20; fvec = vector(mx, i, fibonacci(2*i)); f(n) = if(n <= mx, fvec[n], fibonacci(2*n));
%o A381585 is1(n) = {my(s = 0, m = n, k); while(m > 0, k = 1; while(m > f(k), k++); if(m < f(k), k--); if(m >= 2*f(k), s += 2; m -= 2*f(k), s++; m -= f(k))); !(n % s);}
%o A381585 list(lim) = {my(q1 = is1(1), q2 = is1(2), q3 = is1(3), q4 = is1(4), s5); for(k = 5, lim, q5 = is1(k); if(q1 && q2 && q3 && q4 && q5, print1(k-4, ", ")); q1 = q2; q2 = q3; q3 = q4; q4 = q5);}
%Y A381585 Cf. A291711.
%Y A381585 Subsequence of A381581, A381582, A381583 and A381584.
%Y A381585 Similar sequences: A330928, A334373, A364220, A364383.
%K A381585 nonn,base
%O A381585 1,1
%A A381585 _Amiram Eldar_, Feb 28 2025