A274741 Table of coefficients in functions that satisfy W_n(x) = W_{n-1}(x)^W_n(x), with W_0(x) = exp(x), as read by antidiagonals.
1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 16, 5, 1, 1, 1, 125, 43, 7, 1, 1, 1, 1296, 525, 82, 9, 1, 1, 1, 16807, 8321, 1345, 133, 11, 1, 1, 1, 262144, 162463, 28396, 2729, 196, 13, 1, 1, 1, 4782969, 3774513, 734149, 71721, 4821, 271, 15, 1, 1, 1, 100000000, 101808185, 22485898, 2300485, 151376, 7765, 358, 17, 1, 1, 1, 2357947691, 3129525793, 796769201, 87194689, 5787931, 283321, 11705, 457, 19, 1, 1, 1, 61917364224, 108063152091, 32084546824, 3815719969, 261066156, 12567187, 486396, 16785, 568, 21, 1, 1
Offset: 0
Examples
See examples at A274391, which is the main entry for this table. This table begins: 1, 1, 1, 1, 1, 1, 1, 1, ...; 1, 1, 3, 16, 125, 1296, 16807, 262144, ...; 1, 1, 5, 43, 525, 8321, 162463, 3774513, ...; 1, 1, 7, 82, 1345, 28396, 734149, 22485898, ...; 1, 1, 9, 133, 2729, 71721, 2300485, 87194689, ...; 1, 1, 11, 196, 4821, 151376, 5787931, 261066156, ...; 1, 1, 13, 271, 7765, 283321, 12567187, 656778529, ...; 1, 1, 15, 358, 11705, 486396, 24539593, 1457297878, ...; ... This table may also be written as a triangle: 1; 1, 1; 1, 1, 1; 1, 3, 1, 1; 1, 16, 5, 1, 1; 1, 125, 43, 7, 1, 1; 1, 1296, 525, 82, 9, 1, 1; 1, 16807, 8321, 1345, 133, 11, 1, 1; 1, 262144, 162463, 28396, 2729, 196, 13, 1, 1; 1, 4782969, 3774513, 734149, 71721, 4821, 271, 15, 1, 1; 1, 100000000, 101808185, 22485898, 2300485, 151376, 7765, 358, 17, 1, 1; ...
Crossrefs
Cf. A274391.
Programs
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PARI
{ITERATE(F, n, k) = my(G=x +x*O(x^k)); for(i=1, n, G=subst(G, x, F)); G} {T(n, k) = my(TREE = serreverse(x*exp(-x +x*O(x^k)))); k!*polcoeff(exp(ITERATE(TREE, n, k)), k)} /* Print this table as a rectangular array */ for(n=0, 10, for(k=0, 10, print1(T(n, k), ", ")); print("")) /* Print this table as a triangle */ for(n=0, 12, for(k=0, n, print1(T(k, n-k), ", "));print("") ) /* Print this table as a flattened array */ for(n=0, 12, for(k=0, n, print1(T(k, n-k), ", ")); )
Formula
See formulas at A274391, which is the main entry for this table.
Comments