login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A190633
G.f. satisfies: A(x) = 1 + x*A(x*A(x*A(x*A(x*...x*A(x*...)^n...)^4)^3)^2)^1.
1
1, 1, 1, 3, 16, 118, 1077, 11486, 138444, 1847148, 26912226, 424290217, 7194012328, 130641675418, 2534008088656, 52404312807800, 1154031769467768, 27034986095711172, 673063391032594741, 17786452294614118713, 498174223396072711297, 14762117810503938465521, 461836676823537625928868
OFFSET
0,4
LINKS
EXAMPLE
G.f.: A(x) = 1 + x + x^2 + 3*x^3 + 16*x^4 + 118*x^5 + 1077*x^6 + 11486*x^7 +...
where
A(x) = 1 + x*A(x*B(x)^2)
B(x) = A(x*C(x)^3) = 1 + x + 4*x^2 + 27*x^3 + 242*x^4 + 2613*x^5 +...
C(x) = A(x*D(x)^4) = 1 + x + 5*x^2 + 41*x^3 + 436*x^4 + 5493*x^5 +...
D(x) = A(x*E(x)^5) = 1 + x + 6*x^2 + 58*x^3 + 716*x^4 + 10353*x^5 +...
E(x) = A(x*F(x)^6) = 1 + x + 7*x^2 + 78*x^3 + 1098*x^4 + 17954*x^5 +...
F(x) = A(x*G(x)^7) = 1 + x + 8*x^2 + 101*x^3 + 1598*x^4 + 29182*x^5 +...
...
The coefficients in the functions A_{n}(x) = A(x*A_{n+1}(x)^(n+1)) begin:
n=1: [1, 1, 3, 16, 118, 1077, 11486, 138444, 1847148, ...];
n=2: [1, 1, 4, 27, 242, 2613, 32361, 446981, 6767752, ...];
n=3: [1, 1, 5, 41, 436, 5493, 78411, 1236675, 21220924, ...];
n=4: [1, 1, 6, 58, 716, 10353, 168128, 2995118, 57697373, ...];
n=5: [1, 1, 7, 78, 1098, 17954, 327516, 6516816, 139510116, ...];
n=6: [1, 1, 8, 101, 1598, 29182, 591387, 13012390, 306746446, ...];
n=7: [1, 1, 9, 127, 2232, 45048, 1004657, 24234584, 624104908, ...];
n=8: [1, 1, 10, 156, 3016, 66688, 1623642, 42621080, 1190879427, ...];
n=9: [1, 1, 11, 188, 3966, 95363, 2517354, 71454120, 2153352732, ...];
n=10:[1, 1, 12, 223, 5098, 132459, 3768797, 115036935, 3719861220,...];
n=11:[1, 1, 13, 261, 6428, 179487, 5476263, 178886981, 6178793404,...];
n=12:[1, 1, 14, 302, 7972, 238083, 7754628, 269945982, 9919784089,...];
n=13:[1, 1, 15, 346, 9746, 310008, 10736648, 396806780, 15458366420,...];
n=14:[1, 1, 16, 393, 11766, 397148, 14574255, 569956992, 23464343946,...];
n=15:[1, 1, 17, 443, 14048, 501514, 19439853, 802039474, 34794144844,...];
...
The coefficients in the functions A_{n}(x)^n = A(x*A_{n+1}(x)^(n+1))^n begin:
n=1: [1, 1, 3, 16, 118, 1077, 11486, 138444, 1847148, ...];
n=2: [1, 2, 9, 62, 554, 5926, 72613, 992656, 14888020, ...];
n=3: [1, 3, 18, 154, 1644, 20523, 288977, 4490214, ...];
n=4: [1, 4, 30, 308, 3849, 55332, 886740, 15542428, ...];
n=5: [1, 5, 45, 540, 7755, 126601, 2283415, 44720260, ...];
n=6: [1, 6, 63, 866, 14073, 257658, 5175458, 112225428, ...];
n=7: [1, 7, 84, 1302, 23639, 480207, 10642667, 253418838, ...];
n=8: [1, 8, 108, 1864, 37414, 835624, 20269388, 526168488, ...];
n=9: [1, 9, 135, 2568, 56484, 1376253, 36282528, 1020278988, ...];
n=10:[1, 10, 165, 3430, 82060, 2166702, 61706375, 1869264840, ...];
n=11:[1, 11, 198, 4466, 115478, 3285139, 100534225, 3264729622, ...];
n=12:[1, 12, 234, 5692, 158199, 4824588, 157916816, 5473613220, ...];
n=13:[1, 13, 273, 7124, 211809, 6894225, 240367569, 8858569252, ...];
n=14:[1, 14, 315, 8778, 278019, 9620674, 355984636, 13901734828, ...];
n=15:[1, 15, 360, 10670, 358665, 13149303, 514689755, 21232154790, ...];
...
PROG
(PARI) {a(n)=local(A, G=1+x); for(j=0, n, A=1+x*G; for(i=0, n-1, G=subst(A, x, x*(G+x*O(x^n))^(n-i+1)))); polcoeff(A, n)}
for(n=0, 30, print1(a(n), ", "))
CROSSREFS
Sequence in context: A221409 A074522 A302701 * A220352 A333682 A125807
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Mar 02 2013
STATUS
approved