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%I #32 Feb 15 2020 08:03:37
%S 2,6,15,22,36,58,95,96,147,148,209,210,305,306,901,902,903,904,905,
%T 906,1149,1150,1353,1354,1355,1356,1357,1358,1359,1360,5621,5622,8499,
%U 8500,9585,9586,15719,15720,15721,15722,15723,15724,15725,15726,19653,19654,19655,19656,19657,19658,19659,19660,31449
%N Where record values occur in A276781, when starting from A276781(2)=1.
%C Terms at the end of each run, that is, terms k that are not followed by k+1 (i.e., this excludes terms like 95, 147, 209, 901 .. 905, 1149, ...) form a subsequence of A181062. - _Antti Karttunen_, Jan 20 2020
%H Antti Karttunen, <a href="/A276782/b276782.txt">Table of n, a(n) for n = 1..210</a> (terms 1..72 from Chai Wah Wu)
%H Christophe Soulé, <a href="https://vimeo.com/100212123">Le triangle de Pascal et ses propriétés</a>, Lecture, Soc. Math. de France, Feb 13 2008.
%p A276781 := proc(n)
%p local b,k;
%p for b from 0 to floor(n/2+1) do
%p igcd(seq(binomial(n,k),k=b..n-b)) ;
%p if % > 1 then
%p return b ;
%p end if;
%p end do:
%p end proc:
%p am := -1 ;
%p for n from 2 do
%p an := A276781(n) ;
%p if an > am then
%p printf("%d,\n",n) ;
%p am := an ;
%p end if;
%p end do: # _R. J. Mathar_, Sep 30 2016
%t Function[t, First@ Position[t, #] & /@ Range@ Max@ t][{0}~Join~Table[b = 1; While[GCD @@ Map[Binomial[n, #] &, Range[b, n - b]] == 1, b++]; b, {n, 2, 1500}]] // Flatten (* _Michael De Vlieger_, Oct 03 2016 *)
%o (PARI)
%o A276781(n) = if(1==n,1,forstep(k=n,1,-1,if(isprimepower(k),return(1+n-k))));
%o m=0; k=0; n=1; while(k<210,n++; if((t=A276781(n))>m, m=t; k++; print1(n, ", "))); \\ _Antti Karttunen_, Jan 29 2020
%Y Cf. A181062, A276781.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Sep 29 2016
%E a(11)-a(30) from _R. J. Mathar_, Sep 30 2016
%E More terms from _Chai Wah Wu_, Oct 02 2016
%E Definition amended because of the changed definition of A276781, while keeping the terms same as before. - _Antti Karttunen_, Jan 29 2020
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