cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-10 of 12 results. Next

A275765 G.f. satisfies: A(x - A(x)^2) = x + A(x)^2.

Original entry on oeis.org

1, 2, 12, 106, 1148, 14156, 191400, 2775930, 42585412, 684496988, 11449962008, 198331811356, 3543990791480, 65136985937096, 1228531761076208, 23733123786608826, 468887742020767788, 9461919438245032500, 194817077269127033944, 4089069139317823277548, 87426000975842460304792, 1902787414323673070857528, 42133267254272433484761584, 948695717599714654940068604, 21712101305047777916075831096, 504865916349551192319293625016
Offset: 1

Views

Author

Paul D. Hanna, Aug 31 2016

Keywords

Examples

			G.f.: A(x) = x + 2*x^2 + 12*x^3 + 106*x^4 + 1148*x^5 + 14156*x^6 + 191400*x^7 + 2775930*x^8 + 42585412*x^9 + 684496988*x^10 + 11449962008*x^11 + 198331811356*x^12 +...
such that A(x - A(x)^2) = x + A(x)^2.
RELATED SERIES.
Series_Reversion(x - A(x)^2) = x + x^2 + 6*x^3 + 53*x^4 + 574*x^5 + 7078*x^6 + 95700*x^7 + 1387965*x^8 + 21292706*x^9 + 342248494*x^10 +...
which equals (A(x) + x)/2.
A( (A(x) + x)/2 ) = x + 3*x^2 + 22*x^3 + 221*x^4 + 2634*x^5 + 35086*x^6 + 506356*x^7 + 7773279*x^8 + 125441594*x^9 + 2110832382*x^10 +...
which equals sqrt( (A(x) - x)/2 ).
Let R(x) = Series_Reversion(A(x)) so that R(A(x)) = x,
R(x) = x - 2*x^2 - 4*x^3 - 26*x^4 - 228*x^5 - 2396*x^6 - 28440*x^7 - 369114*x^8 - 5135468*x^9 - 75602108*x^10 - 1167066216*x^11 - 18768202924*x^12 +...
then Series_Reversion(x + A(x)^2) = x/2 + R(x)/2.

Links

Crossrefs

Cf. A277295, A213591, A276364, A276360, A276361, A276362, A276363.

Programs

  • Mathematica
    m = 26; A[_] = 0;
Do[A[x_] = x + 2 A[x/2 + A[x]/2]^2 + O[x]^(m+1) // Normal, {m+1}];
CoefficientList[A[x]/x, x] (* Jean-François Alcover, Sep 30 2019 *)
  • PARI
    {a(n) = my(A=[1], F=x); for(i=1,n, A=concat(A,0); F=x*Ser(A); A[#A] = -polcoeff(subst(F,x,x-F^2) - F^2,#A) );A[n]}
for(n=1,30,print1(a(n),", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + 2 * A( x/2 + A(x)/2 )^2.
(2) A(x) = -x + 2 * Series_Reversion(x - A(x)^2).
(3) R(x) = -x + 2 * Series_Reversion(x + A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x/2 - R(x)/2 ) ) = x/2 + R(x)/2, where R(A(x)) = x.
a(n) = Sum_{k=0..n-1} A277295(n,k)*2^(n-k).

A277300 G.f. satisfies: A(x - A(x)^2) = x + 4*A(x)^2.

Original entry on oeis.org

1, 5, 60, 1000, 19970, 448160, 10926360, 283651245, 7740058300, 220046970860, 6476695275680, 196438030797880, 6117627849485360, 195082685133612800, 6355848358118392400, 211189970909192038500, 7146354688384980282000, 245970478274041025623200, 8602606263466490521359400, 305460999044315834902424200, 11003870605124169641012461600
Offset: 1

Views

Author

Paul D. Hanna, Oct 09 2016

Keywords

Examples

			G.f.: A(x) = x + 5*x^2 + 60*x^3 + 1000*x^4 + 19970*x^5 + 448160*x^6 + 10926360*x^7 + 283651245*x^8 + 7740058300*x^9 + 220046970860*x^10 +...

Links

Crossrefs

Cf. A277295, A213591, A275765, A276360, A276361, A276362, A276363.
Cf. A277301, A277302, A277303, A277304, A277305, A277306, A277307, A277308, A277309.
Cf. A276364.

Programs

  • Mathematica
    m = 22; A[_] = 0;
Do[A[x_] = x + 5 A[4x/5 + A[x]/5]^2 + O[x]^m // Normal, {m}];
CoefficientList[A[x]/x, x] (* Jean-François Alcover, Sep 30 2019 *)
  • PARI
    {a(n) = my(A=[1], F=x); for(i=1, n, A=concat(A, 0); F=x*Ser(A); A[#A] = -polcoeff(subst(F, x, x - F^2) - 4*F^2, #A) ); A[n]}
for(n=1, 30, print1(a(n), ", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + 5 * A( 4*x/5 + A(x)/5 )^2.
(2) A(x) = -4*x + 5 * Series_Reversion(x - A(x)^2).
(3) R(x) = -x/4 + 5/4 * Series_Reversion(x + 4*A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x/5 - R(x)/5 ) ) = x/5 + 4*R(x)/5, where R(A(x)) = x.
a(n) = Sum_{k=0..n-1} A277295(n,k) * 5^(n-k-1).

A277301 G.f. satisfies: A(x - 2*A(x)^2) = x + 3*A(x)^2.

Original entry on oeis.org

1, 5, 70, 1425, 35410, 999210, 30855820, 1020407105, 35642665050, 1302725802510, 49490450201460, 1944619121474970, 78734794663758580, 3275324221277662900, 139667810517388712600, 6093781146211490413825, 271623891311306597652650, 12353670814537544856558950, 572686428900679117724156900, 27036308383662996662940155550, 1298856469077709523772645582300
Offset: 1

Views

Author

Paul D. Hanna, Oct 09 2016

Keywords

Examples

			G.f.: A(x) = x + 5*x^2 + 70*x^3 + 1425*x^4 + 35410*x^5 + 999210*x^6 + 30855820*x^7 + 1020407105*x^8 + 35642665050*x^9 + 1302725802510*x^10 +...

Links

Crossrefs

Cf. A277295, A213591, A275765, A276360, A276361, A276362, A276363.
Cf. A277300, A277302, A277303, A277304, A277305, A277306, A277307, A277308, A277309.
Cf. A276364.

Programs

  • PARI
    {a(n) = my(A=[1], F=x); for(i=1, n, A=concat(A, 0); F=x*Ser(A); A[#A] = -polcoeff(subst(F, x, x - 2*F^2) - 3*F^2, #A) ); A[n]}
for(n=1, 30, print1(a(n), ", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + 5 * A( 3*x/5 + 2*A(x)/5 )^2.
(2) A(x) = -3*x/2 + 5/2 * Series_Reversion(x - 2*A(x)^2).
(3) R(x) = -2*x/3 + 5/3 * Series_Reversion(x + 3*A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x/5 - R(x)/5 ) ) = 2*x/5 + 3*R(x)/5, where R(A(x)) = x.
a(n) = Sum_{k=0..n-1} A277295(n,k) * 2^k * 5^(n-k-1).

A277302 G.f. satisfies: A(x - 3*A(x)^2) = x + 2*A(x)^2.

Original entry on oeis.org

1, 5, 80, 1900, 55490, 1848660, 67630080, 2657251005, 110560510400, 4824793769260, 219334788340040, 10334817935549420, 502814686712631520, 25184673137026274600, 1295595210394570426800, 68326193725188929358600, 3688253200687778850553800, 203524353764195058692833200, 11468618360097679305600299400, 659345494779348103800864088800, 38644445208422874351089132287200
Offset: 1

Views

Author

Paul D. Hanna, Oct 09 2016

Keywords

Examples

			G.f.: A(x) = x + 5*x^2 + 80*x^3 + 1900*x^4 + 55490*x^5 + 1848660*x^6 + 67630080*x^7 + 2657251005*x^8 + 110560510400*x^9 + 4824793769260*x^10 +...

Links

Crossrefs

Cf. A277295, A213591, A275765, A276360, A276361, A276362, A276363.
Cf. A277300, A277301, A277303, A277304, A277305, A277306, A277307, A277308, A277309.
Cf. A276364.

Programs

  • PARI
    {a(n) = my(A=[1], F=x); for(i=1, n, A=concat(A, 0); F=x*Ser(A); A[#A] = -polcoeff(subst(F, x, x - 3*F^2) - 2*F^2, #A) ); A[n]}
for(n=1, 30, print1(a(n), ", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + 5 * A( 2*x/5 + 3*A(x)/5 )^2.
(2) A(x) = -2*x/3 + 5/3 * Series_Reversion(x - 3*A(x)^2).
(3) R(x) = -3*x/2 + 5/2 * Series_Reversion(x + 2*A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x/5 - R(x)/5 ) ) = 3*x/5 + 2*R(x)/5, where R(A(x)) = x.
a(n) = Sum_{k=0..n-1} A277295(n,k) * 3^k * 5^(n-k-1).

A277303 G.f. satisfies: A(x - 4*A(x)^2) = x + A(x)^2.

Original entry on oeis.org

1, 5, 90, 2425, 80630, 3065810, 128271540, 5774538945, 275743894750, 13832116773110, 723891526915820, 39323723086794730, 2208811824884144540, 127904686371063157700, 7617441454740093233000, 465691699545009287055825, 29179499379365501297165550, 1871486497257264286902367950, 122731222232573572625823907900, 8222122259910817121846641763950, 562251437460415648354364719018900
Offset: 1

Views

Author

Paul D. Hanna, Oct 09 2016

Keywords

Examples

			G.f.: A(x) = x + 5*x^2 + 90*x^3 + 2425*x^4 + 80630*x^5 + 3065810*x^6 + 128271540*x^7 + 5774538945*x^8 + 275743894750*x^9 + 13832116773110*x^10 +...

Links

Crossrefs

Cf. A277295, A213591, A275765, A276360, A276361, A276362, A276363.
Cf. A277300, A277301, A277302, A277304, A277305, A277306, A277307, A277308, A277309.
Cf. A276364.

Programs

  • PARI
    {a(n) = my(A=[1], F=x); for(i=1, n, A=concat(A, 0); F=x*Ser(A); A[#A] = -polcoeff(subst(F, x, x - 4*F^2) - F^2, #A) ); A[n]}
for(n=1, 30, print1(a(n), ", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + 5 * A( x/5 + 4*A(x)/5 )^2.
(2) A(x) = -x/4 + 5/4 * Series_Reversion(x - 4*A(x)^2).
(3) R(x) = -4*x + 5 * Series_Reversion(x + A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x/5 - R(x)/5 ) ) = 4*x/5 + R(x)/5, where R(A(x)) = x.
a(n) = Sum_{k=0..n-1} A277295(n,k) * 4^k * 5^(n-k-1).

A277304 G.f. satisfies: A(x - A(x)^2) = x + 5*A(x)^2.

Original entry on oeis.org

1, 6, 84, 1614, 36948, 947412, 26334072, 778107150, 24133349532, 778923367284, 26000354998920, 893459845502916, 31496296778304936, 1135911643635146712, 41820127450763818896, 1568983653501973667262, 59898843849911992994340, 2324166762372316001442540, 91565378725229449617874824, 3659689884915567083966937156, 148284110214725433666804447912
Offset: 1

Views

Author

Paul D. Hanna, Oct 09 2016

Keywords

Examples

			G.f.: A(x) = x + 6*x^2 + 84*x^3 + 1614*x^4 + 36948*x^5 + 947412*x^6 + 26334072*x^7 + 778107150*x^8 + 24133349532*x^9 + 778923367284*x^10 +...

Links

Crossrefs

Cf. A277295, A213591, A275765, A276360, A276361, A276362, A276363.
Cf. A277300, A277301, A277302, A277303, A277305, A277306, A277307, A277308, A277309.
Cf. A276364.

Programs

  • PARI
    {a(n) = my(A=[1], F=x); for(i=1, n, A=concat(A, 0); F=x*Ser(A); A[#A] = -polcoeff(subst(F, x, x - F^2) - 5*F^2, #A) ); A[n]}
for(n=1, 30, print1(a(n), ", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + 6 * A( 5*x/6 + A(x)/6 )^2.
(2) A(x) = -5*x + 6 * Series_Reversion(x - A(x)^2).
(3) R(x) = -x/5 + 6/5 * Series_Reversion(x + 5*A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x/6 - R(x)/6 ) ) = x/6 + 5*R(x)/6, where R(A(x)) = x.
a(n) = Sum_{k=0..n-1} A277295(n,k) * 6^(n-k-1).

A277305 G.f. satisfies: A(x - 5*A(x)^2) = x + A(x)^2.

Original entry on oeis.org

1, 6, 132, 4350, 176964, 8235252, 421814232, 23252672574, 1359954622860, 83572511671092, 5359130778285096, 356786692299782916, 24565803644793789192, 1744056102774572824920, 127369971591949093219920, 9550397045409732902387790, 734084078724419876468356500, 57766855968717521513179054860, 4648888743682938087701732224680
Offset: 1

Views

Author

Paul D. Hanna, Oct 09 2016

Keywords

Examples

			G.f.: A(x) = x + 6*x^2 + 132*x^3 + 4350*x^4 + 176964*x^5 + 8235252*x^6 + 421814232*x^7 + 23252672574*x^8 + 1359954622860*x^9 + 83572511671092*x^10 +...

Links

Crossrefs

Cf. A277295, A213591, A275765, A276360, A276361, A276362, A276363.
Cf. A277300, A277301, A277302, A277303, A277304, A277306, A277307, A277308, A277309.
Cf. A276364.

Programs

  • PARI
    {a(n) = my(A=[1], F=x); for(i=1, n, A=concat(A, 0); F=x*Ser(A); A[#A] = -polcoeff(subst(F, x, x - 5*F^2) - F^2, #A) ); A[n]}
for(n=1, 30, print1(a(n), ", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + 6 * A( x/6 + 5*A(x)/6 )^2.
(2) A(x) = -x/5 + 6/5 * Series_Reversion(x - 5*A(x)^2).
(3) R(x) = -5*x + 6 * Series_Reversion(x + A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x/6 - R(x)/6 ) ) = 5*x/6 + R(x)/6, where R(A(x)) = x.
a(n) = Sum_{k=0..n-1} A277295(n,k) * 5^k * 6^(n-k-1).

A277306 G.f. satisfies: A(x + A(x)^2) = x + 2*A(x)^2.

Original entry on oeis.org

1, 1, 0, -4, 2, 52, -96, -975, 4240, 18460, -183448, -101716, 7373216, -23650520, -230147920, 2198499720, 664806792, -124144328784, 703989911368, 3189500786336, -68800373946656, 284782780974128, 2913071885553608, -47063844278787824, 170357147598919640, 2621783446017272624, -41775596442709927664, 166446909354828214608
Offset: 1

Views

Author

Paul D. Hanna, Oct 09 2016

Keywords

Examples

			G.f.: A(x) = x + x^2 - 4*x^4 + 2*x^5 + 52*x^6 - 96*x^7 - 975*x^8 + 4240*x^9 + 18460*x^10 - 183448*x^11 - 101716*x^12 + 7373216*x^13 - 23650520*x^14 - 230147920*x^15 + 2198499720*x^16 + 664806792*x^17 - 124144328784*x^18 + 703989911368*x^19 + 3189500786336*x^20 +...
such that
A(x + A(x)^2) = x + 2*A(x)^2
also,
A(x) = x + A( 2*x - A(x) )^2.
RELATED SERIES.
A(x)^2 = x^2 + 2*x^3 + x^4 - 8*x^5 - 4*x^6 + 108*x^7 - 72*x^8 - 2158*x^9 + 6118*x^10 + 46376*x^11 - 319856*x^12 - 618132*x^13 + 14320096*x^14 - 30385024*x^15 - 505460559*x^16 + 3846420096*x^17 + 5951934200*x^18 - 243911854368*x^19 + 1136290742936*x^20 +...
A(x + A(x)^2) = x + 2*x^2 + 4*x^3 + 2*x^4 - 16*x^5 - 8*x^6 + 216*x^7 - 144*x^8 - 4316*x^9 + 12236*x^10 + 92752*x^11 - 639712*x^12 +...
which equals x + 2*A(x)^2.
Series_Reversion(A(x)) = x - x^2 + 2*x^3 - x^4 - 12*x^5 + 32*x^6 + 156*x^7 - 1140*x^8 - 1178*x^9 + 41270*x^10 - 105480*x^11 - 1274828*x^12 + 10307292*x^13 + 13297704*x^14 - 609624768*x^15 + 2614447647*x^16 + 21136068780*x^17 - 300421913212*x^18 + 590894313656*x^19 + 17309654827168*x^20 +...
which equals 2*x - Series_Reversion(x + 2*A(x)^2).

Links

Crossrefs

Cf. A277295, A213591, A275765, A276360, A276361, A276362, A276363.
Cf. A277300, A277301, A277302, A277303, A277304, A277305, A277307, A277308, A277309, A277310, A277311.
Cf. A276364.

Programs

  • PARI
    {a(n) = my(A=[1], F=x); for(i=1, n, A=concat(A, 0); F=x*Ser(A); A[#A] = -polcoeff(subst(F, x, x + F^2) - 2*F^2, #A) ); A[n]}
for(n=1, 30, print1(a(n), ", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + A( 2*x - A(x) )^2.
(2) A(x) = 2*x - Series_Reversion(x + A(x)^2).
(3) R(x) = x/2 + 1/2 * Series_Reversion(x + 2*A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x - R(x) ) ) = -x + 2*R(x), where R(A(x)) = x.
(5) A(x) = x + Sum_{n>=1} (-1)^(n-1) * d^(n-1)/dx^(n-1) A(x)^(2*n) / n!.
a(n) = Sum_{k=0..n-1} (-1)^k * A277295(n,k).

A277307 G.f. satisfies: A(x - 3*A(x)^2) = x - 2*A(x)^2.

Original entry on oeis.org

1, 1, 8, 92, 1298, 20988, 375120, 7252065, 149534312, 3256987724, 74418884792, 1774657501252, 43995940957120, 1130453689908568, 30031716838365552, 823263454676130312, 23249951990747403528, 675517165191231019920, 20168579968950108809736, 618158189347428262782816, 19432224179107494743506272, 626034612821085407187912624
Offset: 1

Views

Author

Paul D. Hanna, Oct 09 2016

Keywords

Examples

			G.f.: A(x) = x + x^2 + 8*x^3 + 92*x^4 + 1298*x^5 + 20988*x^6 + 375120*x^7 + 7252065*x^8 + 149534312*x^9 + 3256987724*x^10 +...
such that A(x - 3*A(x)^2) = x - 2*A(x)^2.
RELATED SERIES.
A(x)^2 = x^2 + 2*x^3 + 17*x^4 + 200*x^5 + 2844*x^6 + 46044*x^7 + 821448*x^8 + 15829010*x^9 + 325121270*x^10 + 7052584040*x^11 + 160492981648*x^12 + 3812351286940*x^13 + 94164503583424*x^14 + 2411159638210752*x^15 + 63849498902714289*x^16 +...
A(x - 3*A(x)^2) = x - 2*x^2 - 4*x^3 - 34*x^4 - 400*x^5 - 5688*x^6 - 92088*x^7 - 1642896*x^8 - 31658020*x^9 - 650242540*x^10 +...
which equals x - 2*A(x)^2.
Series_Reversion(x - 3*A(x)^2) = x + 3*x^2 + 24*x^3 + 276*x^4 + 3894*x^5 + 62964*x^6 + 1125360*x^7 + 21756195*x^8 + 448602936*x^9 + 9770963172*x^10 +...
which equals -2*x + 3*A(x).
A( 3*A(x) - 2*x ) = x + 4*x^2 + 38*x^3 + 497*x^4 + 7784*x^5 + 137538*x^6 + 2656584*x^7 + 55045728*x^8 + 1208709044*x^9 + 27891950516*x^10 +...
which equals sqrt( A(x) - x ).

Links

Crossrefs

Cf. A277295, A213591, A275765, A276360, A276361, A276362, A276363.
Cf. A277300, A277301, A277302, A277303, A277304, A277305, A277306, A277308, A277309.
Cf. A276364.

Programs

  • PARI
    {a(n) = my(A=[1], F=x); for(i=1, n, A=concat(A, 0); F=x*Ser(A); A[#A] = -polcoeff(subst(F, x, x-3*F^2) + 2*F^2, #A) ); A[n]}
for(n=1, 30, print1(a(n), ", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + A( 3*A(x) - 2*x )^2.
(2) A(x) = 2*x/3 + 1/3 * Series_Reversion(x - 3*A(x)^2).
(3) R(x) = 3*x/2 - 1/2 * Series_Reversion(x - 2*A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x - R(x) ) ) = 3*x - 2*R(x), where R(A(x)) = x.
(5) A(x) = x + Sum_{n>=1} 3^(n-1) * d^(n-1)/dx^(n-1) A(x)^(2*n) / n!.
a(n) = Sum_{k=0..n-1} A277295(n,k) * 3^k.

A277308 G.f. satisfies: A(x - 3*A(x)^2) = x - A(x)^2.

Original entry on oeis.org

1, 2, 20, 298, 5492, 116124, 2710776, 68308170, 1831522940, 51744512380, 1529687560328, 47075470016012, 1502258036769256, 49560341916549320, 1686236991420431760, 59054595629732284890, 2125432920387784135812, 78509698415432235272292, 2972996232264052816975752, 115303660044380692013332428
Offset: 1

Views

Author

Paul D. Hanna, Oct 09 2016

Keywords

Examples

			G.f.: A(x) = x + 2*x^2 + 20*x^3 + 298*x^4 + 5492*x^5 + 116124*x^6 + 2710776*x^7 + 68308170*x^8 + 1831522940*x^9 + 51744512380*x^10 +...

Links

Crossrefs

Cf. A277295, A213591, A275765, A276360, A276361, A276362, A276363.
Cf. A277300, A277301, A277302, A277303, A277304, A277305, A277306, A277307, A277309.
Cf. A276364.

Programs

  • PARI
    {a(n) = my(A=[1], F=x); for(i=1, n, A=concat(A, 0); F=x*Ser(A); A[#A] = -polcoeff(subst(F, x, x-3*F^2) + F^2, #A) ); A[n]}
for(n=1, 30, print1(a(n), ", "))

Formula

G.f. A(x) also satisfies:
(1) A(x) = x + 2 * A( 3*A(x)/2 - x/2 )^2.
(2) A(x) = x/3 + 2/3 * Series_Reversion(x - 3*A(x)^2).
(3) R(x) = 3*x - 2 * Series_Reversion(x - A(x)^2), where R(A(x)) = x.
(4) R( sqrt( x/2 - R(x)/2 ) ) = 3*x/2 - R(x)/2, where R(A(x)) = x.
a(n) = Sum_{k=0..n-1} A277295(n,k) * 3^k * 2^(n-k-1).
Showing 1-10 of 12 results. Next

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