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 1-8 of 8 results.

A341191 Number of ways to write n as an ordered sum of 2 nonzero decimal palindromes.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 9, 8, 7, 6, 5, 4, 3, 2, 2, 0, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 4, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 5, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 6, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 7, 2, 2
Offset: 2

Views

Author

Ilya Gutkovskiy, Feb 06 2021

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 90; CoefficientList[Series[Sum[Boole[PalindromeQ[k]] x^k, {k, 1, nmax}]^2, {x, 0, nmax}], x] // Drop[#, 2] &

A341192 Number of ways to write n as an ordered sum of 3 nonzero decimal palindromes.

Original entry on oeis.org

1, 3, 6, 10, 15, 21, 28, 36, 45, 52, 60, 66, 70, 72, 72, 70, 66, 60, 55, 45, 39, 34, 30, 27, 25, 24, 24, 24, 27, 27, 25, 27, 27, 27, 27, 27, 27, 27, 27, 30, 27, 27, 30, 30, 30, 30, 30, 30, 30, 30, 33, 27, 30, 33, 33, 33, 33, 33, 33, 33, 33, 36, 27, 34, 36, 36, 36, 36
Offset: 3

Views

Author

Ilya Gutkovskiy, Feb 06 2021

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 70; CoefficientList[Series[Sum[Boole[PalindromeQ[k]] x^k, {k, 1, nmax}]^3, {x, 0, nmax}], x] // Drop[#, 3] &

A341184 Number of ways to write n as an ordered sum of 5 nonzero decimal palindromes.

Original entry on oeis.org

1, 5, 15, 35, 70, 126, 210, 330, 495, 710, 981, 1310, 1695, 2130, 2605, 3106, 3615, 4110, 4575, 4980, 5311, 5555, 5705, 5760, 5725, 5611, 5435, 5210, 4975, 4735, 4511, 4320, 4170, 4065, 4005, 3986, 4005, 4040, 4100, 4175, 4241, 4310, 4380, 4450, 4520, 4590, 4665, 4740, 4810
Offset: 5

Views

Author

Ilya Gutkovskiy, Feb 06 2021

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 53; CoefficientList[Series[Sum[Boole[PalindromeQ[k]] x^k, {k, 1, nmax}]^5, {x, 0, nmax}], x] // Drop[#, 5] &

A341203 Number of ways to write n as an ordered sum of 6 nonzero decimal palindromes.

Original entry on oeis.org

1, 6, 21, 56, 126, 252, 462, 792, 1287, 1996, 2973, 4272, 5942, 8022, 10536, 13488, 16857, 20592, 24622, 28836, 33108, 37298, 41262, 44862, 47976, 50508, 52398, 53612, 54192, 54186, 53688, 52818, 51708, 50492, 49296, 48228, 47383, 46788, 46497, 46506, 46773, 47268, 47948
Offset: 6

Views

Author

Ilya Gutkovskiy, Feb 06 2021

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 48; CoefficientList[Series[Sum[Boole[PalindromeQ[k]] x^k, {k, 1, nmax}]^6, {x, 0, nmax}], x] // Drop[#, 6] &

A341204 Number of ways to write n as an ordered sum of 7 nonzero decimal palindromes.

Original entry on oeis.org

1, 7, 28, 84, 210, 462, 924, 1716, 3003, 4998, 7966, 12222, 18123, 26054, 36408, 49560, 65835, 85470, 108591, 135163, 164976, 197632, 232547, 268968, 306005, 342678, 377979, 410914, 440630, 466417, 487788, 504511, 516621, 524412, 528409, 529320, 528003, 525308, 522144
Offset: 7

Views

Author

Ilya Gutkovskiy, Feb 06 2021

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 45; CoefficientList[Series[Sum[Boole[PalindromeQ[k]] x^k, {k, 1, nmax}]^7, {x, 0, nmax}], x] // Drop[#, 7] &

A341205 Number of ways to write n as an ordered sum of 8 nonzero decimal palindromes.

Original entry on oeis.org

1, 8, 36, 120, 330, 792, 1716, 3432, 6435, 11432, 19392, 31592, 49652, 75552, 111624, 160512, 225093, 308352, 413232, 542424, 698146, 881912, 1094312, 1334824, 1601679, 1891800, 2200836, 2523256, 2852636, 3181936, 3503900, 3811488, 4098313, 4359048, 4589768, 4788192, 4953860
Offset: 8

Views

Author

Ilya Gutkovskiy, Feb 06 2021

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 44; CoefficientList[Series[Sum[Boole[PalindromeQ[k]] x^k, {k, 1, nmax}]^8, {x, 0, nmax}], x] // Drop[#, 8] &

A341206 Number of ways to write n as an ordered sum of 9 nonzero decimal palindromes.

Original entry on oeis.org

1, 9, 45, 165, 495, 1287, 3003, 6435, 12870, 24301, 43686, 75249, 124809, 200115, 311157, 470415, 693000, 996633, 1401436, 1929465, 2603979, 3448440, 4485267, 5734395, 7211718, 8927523, 10885050, 13079257, 15496065, 18112050, 20894757, 23803659, 26791749, 29807697, 32798448
Offset: 9

Views

Author

Ilya Gutkovskiy, Feb 06 2021

Keywords

Crossrefs

Programs

  • Maple
    p:= proc(n) option remember; local i, s; s:= ""||n;
          for i to iquo(length(s), 2) do if
            s[i]<>s[-i] then return false fi od; true
        end:
    b:= proc(n, t) option remember; `if`(n=0, `if`(t=0, 1, 0),
          `if`(t<1, 0, add(`if`(p(j), b(n-j, t-1), 0), j=1..n)))
        end:
    a:= n-> b(n, 9):
    seq(a(n), n=9..43);  # Alois P. Heinz, Feb 07 2021
  • Mathematica
    nmax = 43; CoefficientList[Series[Sum[Boole[PalindromeQ[k]] x^k, {k, 1, nmax}]^9, {x, 0, nmax}], x] // Drop[#, 9] &

A341207 Number of ways to write n as an ordered sum of 10 nonzero decimal palindromes.

Original entry on oeis.org

1, 10, 55, 220, 715, 2002, 5005, 11440, 24310, 48610, 92288, 167500, 292180, 491920, 802120, 1270324, 1958605, 2945800, 4329370, 6226580, 8774695, 12129890, 16464610, 21963190, 28815655, 37209766, 47321560, 59304730, 73279565, 89322100, 107454362, 127636600, 149762345, 173657020
Offset: 10

Views

Author

Ilya Gutkovskiy, Feb 06 2021

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 43; CoefficientList[Series[Sum[Boole[PalindromeQ[k]] x^k, {k, 1, nmax}]^10, {x, 0, nmax}], x] // Drop[#, 10] &
Showing 1-8 of 8 results.