Original entry on oeis.org
1, 1, 4, 27, 254, 3062, 45052, 783151, 15712342, 357459042, 9094926988, 255939571048, 7893741230500, 264806871279676, 9600056691219936, 374033821840909263, 15586672520501193866, 691789220336675178652
Offset: 0
-
{a(n)=local(F=x, CAT=serreverse(x-x^2+x*O(x^(n+2))),M,N,P);M=matrix(n+2, n+2, r, c, F=x; for(i=1, r+c-2, F=subst(F, x, CAT)); polcoeff(F, c)); N=matrix(n+1, n+1, r, c, M[r, c]); P=matrix(n+1, n+1, r, c, M[r+1, c]); (P~*N~^-1)[n+1,1]}
Original entry on oeis.org
1, 2, 11, 94, 1072, 15212, 257777, 5074738, 113775490, 2861365660, 79763482974, 2440866020252, 81343355108428, 2932370770780016, 113695507437209845, 4717853729131352186, 208615291319607614600, 9792578421235713418464
Offset: 0
-
{a(n)=local(F=x, CAT=serreverse(x-x^2+x*O(x^(n+3))),M,N,P);M=matrix(n+3, n+3, r, c, F=x; for(i=1, r+c-2, F=subst(F, x, CAT)); polcoeff(F, c)); N=matrix(n+2, n+2, r, c, M[r, c]); P=matrix(n+2, n+2, r, c, M[r+1, c]); (P~*N~^-1)[n+2,2]}
Original entry on oeis.org
1, 4, 34, 412, 6325, 116372, 2483706, 60168736, 1628677692, 48672911296, 1590752204044, 56418074957840, 2157411204773415, 88464995576660084, 3871611011946560294, 180101399407072883012, 8873328068327122625596
Offset: 0
-
{a(n)=local(F=x, CAT=serreverse(x-x^2+x*O(x^(n+5))),M,N,P);M=matrix(n+5, n+5, r, c, F=x; for(i=1, r+c-2, F=subst(F, x, CAT)); polcoeff(F, c)); N=matrix(n+4, n+4, r, c, M[r, c]); P=matrix(n+4, n+4, r, c, M[r+1, c]); (P~*N~^-1)[n+4,4]}
Original entry on oeis.org
1, 2, 7, 42, 374, 4391, 63637, 1095362, 21823226, 493898216, 12515588806, 351062669154, 10798972965266, 361471373319171, 13080119556342713, 508813238759275712, 21174032937728251318, 938646693399848483498
Offset: 0
-
{a(n)=local(F=x, CAT=serreverse(x-x^2+x*O(x^(n+2))), M, N, P); M=matrix(n+2, n+2, r, c, F=x; for(i=1, r+c-2, F=subst(F, x, CAT)); polcoeff(F, c)); N=matrix(n+1, n+1, r, c, M[r, c]); P=matrix(n+1, n+1, r, c, M[r+1, c]); sum(k=0,n,(P~*N~^-1)[n+1, k+1])}
A158827
The 4th iteration of x*C(x) where C(x) is the Catalan function (A000108).
Original entry on oeis.org
1, 4, 20, 110, 640, 3870, 24084, 153306, 993978, 6544242, 43652340, 294469974, 2006018748, 13784115468, 95444016984, 665407010349, 4667570034444, 32922870719664, 233389493503968, 1662048903052380, 11885333877149532
Offset: 1
-
{a(n)=local(F=serreverse(x-x^2+O(x^(n+1))),G=x); for(i=1,4,G=subst(F,x,G));polcoeff(G,n)}
A158828
The 5th iteration of x*C(x) where C(x) is the Catalan function (A000108).
Original entry on oeis.org
1, 5, 30, 195, 1330, 9380, 67844, 500619, 3755156, 28558484, 219767968, 1708590960, 13403300208, 105983648060, 844009565176, 6764300053390, 54525119251104, 441811163402124, 3597005618194848, 29412560840221272
Offset: 1
-
{a(n)=local(F=serreverse(x-x^2+O(x^(n+1))),G=x); for(i=1,5,G=subst(F,x,G));polcoeff(G,n)}
Original entry on oeis.org
1, 3, 21, 217, 2904, 47337, 906557, 19910808, 492818850, 13564326950, 410807572044, 13573135469214, 485765085176420, 18717987193565613, 772565258231236269, 34002334709760133807, 1589555183231724515700
Offset: 0
-
{a(n)=local(F=x, CAT=serreverse(x-x^2+x*O(x^(n+4))),M,N,P);M=matrix(n+4, n+4, r, c, F=x; for(i=1, r+c-2, F=subst(F, x, CAT)); polcoeff(F, c)); N=matrix(n+3, n+3, r, c, M[r, c]); P=matrix(n+3, n+3, r, c, M[r+1, c]); (P~*N~^-1)[n+3,3]}
Original entry on oeis.org
1, 4, 33, 380, 5510, 95732, 1933288, 44437080, 1144564278, 32638644236, 1020503373032, 34708182795156, 1275532011982176, 50365443858930384, 2126358227959866224, 95577781657788563192, 4556923094838105968302
Offset: 0
-
{a(n)=local(F=x, G=serreverse(x-x^2+O(x^(n+4))), M, N, P, m=n); M=matrix(m+3, m+3, r, c, F=x;for(i=1, r+c-2, F=subst(F, x, G+x*O(x^(m+3)))); polcoeff(F, c)); N=matrix(m+2, m+2, r, c, F=x;for(i=1, r, F=subst(F, x, G+x*O(x^(m+3)))); polcoeff(F, c)); P=matrix(m+2, m+2, r, c, M[r+1, c]); (P~*N~^-1)[n+2, 2]}
Original entry on oeis.org
1, 9, 108, 1610, 28560, 586320, 13658904, 355787568, 10243342296, 322939137312, 11063339361360, 409194048521778, 16249995494795920, 689585033717023224, 31140529927119263136, 1490994828293677370148, 75444108490820383882392
Offset: 0
-
{a(n)=local(F=x, G=serreverse(x-x^2+O(x^(n+5))), M, N, P, m=n); M=matrix(m+4, m+4, r, c, F=x;for(i=1, r+c-2, F=subst(F, x, G+x*O(x^(m+4)))); polcoeff(F, c)); N=matrix(m+3, m+3, r, c, F=x;for(i=1, r, F=subst(F, x, G+x*O(x^(m+4)))); polcoeff(F, c)); P=matrix(m+3, m+3, r, c, M[r+1, c]); (P~*N~^-1)[n+3, 3]}
Original entry on oeis.org
1, 16, 270, 5148, 110929, 2677008, 71648322, 2107966432, 67649839664, 2352412120760, 88122951915388, 3538364803586104, 151611580761978784, 6905283671128114400, 333151832685664811338, 16973306740660778801468
Offset: 0
-
{a(n)=local(F=x, G=serreverse(x-x^2+O(x^(n+6))), M, N, P, m=n); M=matrix(m+5, m+5, r, c, F=x;for(i=1, r+c-2, F=subst(F, x, G+x*O(x^(m+5)))); polcoeff(F, c)); N=matrix(m+4, m+4, r, c, F=x;for(i=1, r, F=subst(F, x, G+x*O(x^(m+5)))); polcoeff(F, c)); P=matrix(m+4, m+4, r, c, M[r+1, c]); (P~*N~^-1)[n+4, 4]}
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