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 1-9 of 9 results.

A061912 a(n) is the smallest m for which sqrt(sum of digits of m^2) = n.

Original entry on oeis.org

0, 1, 2, 3, 13, 67, 264, 1667, 16667, 94863, 1643167, 29983327, 706399164, 31144643167, 1296109172867, 62441868958167, 6927459779738887, 447213595487659543, 77453069648658793167, 14104963594032775808167, 3146266035952345970972687
Offset: 0

Views

Author

Asher Auel, May 17 2001

Keywords

Comments

a(15) <= 62441868958167. - Donovan Johnson, Jul 10 2012
a(21) <= 29999999949999914454883190583. a(22) <= 948566760423324122079007168333. - Zhining Yang, Jun 21 2024

Examples

			Sum of digits of 13^2 = sum of digits of 169 = 16 is the first occurrence of 4^2, so a(4) = 13.
		

Crossrefs

Programs

  • Maple
    f := []: a := 1: for i from 1 to 10 do for j from 1 do if sqrt(convert(convert(j^2,base,10),`+`)) = i then f := [op(f),j]; a := j; break fi; od; od; f;
  • Mathematica
    t={}; m=0; Do[While[Sqrt[Total[IntegerDigits[m^2]]] != n, m++]; AppendTo[t, m], {n,0,9}]; t (* Jayanta Basu, May 06 2013 *)
  • PARI
    a(n) = my(k=0); while(sumdigits(k^2) != n^2, k++); k; \\ Michel Marcus, Jan 07 2017

Extensions

a(11) from John W. Layman, Jan 10 2002
a(12) from Ryan Propper, Jul 07 2005
a(13) from Zak Seidov, Jan 27 2011
a(14) from Donovan Johnson, Jul 10 2012
a(15)-a(20) from Zhining Yang, Jun 21 2024

A107679 Numbers n such that sum of digits of n^3 is 2^3 = 8.

Original entry on oeis.org

2, 5, 8, 11, 20, 50, 80, 101, 110, 200, 500, 800, 1001, 1010, 1100, 2000, 5000, 8000, 10001, 10010, 10100, 11000, 20000, 50000, 80000, 100001, 100010, 100100, 101000, 110000, 200000, 500000, 800000, 1000001, 1000010, 1000100, 1001000, 1010000, 1100000
Offset: 1

Views

Author

Zak Seidov, Jun 10 2005

Keywords

Crossrefs

Cf. A004164 (sum of digits of cubes), A067075, A159462, A159463.

Programs

  • Magma
    [ n: n in [1..2*10^6] | 8 eq (&+Intseq(n^3)) ]; // Vincenzo Librandi, Aug 13 2017
  • Mathematica
    Do[If[Total[IntegerDigits[m^3]]==8, Print[m]], {m, 2*10^7}] (* Vincenzo Librandi, Aug 13 2017 *)
  • PARI
    isok(n) = sumdigits(n^3) == 8; \\ Michel Marcus, Aug 12 2017
    

Extensions

More terms from Michel Marcus, Oct 09 2013

A159462 Numbers n with property that sod(n^3) = 5^3.

Original entry on oeis.org

341075, 423299, 446423, 542657, 638144, 661529, 667163, 786599, 798899, 828113, 837719, 841733, 842921, 861683, 869513, 879353, 883595, 887813, 887819, 905882, 912176, 912299, 919676, 923144, 927926, 928259, 928298, 943538, 950216, 954635
Offset: 1

Views

Author

Zak Seidov, Apr 12 2009

Keywords

Comments

Numbers n with property that A007953(n^3) = 5^3.

Examples

			341075^3 = 39677989979796875, 3+9+6+7+7+9+8+9+9+7+9+7+9+6+8+7+5 = 125 = 5^3.
		

Crossrefs

Cf. A054966 Numbers that are congruent to {0, 1, 8} mod 9. A054966 Possible sums of digits of cubes. A067075 a(n) = smallest number m such that the sum of the digits of m^3 is equal to n^3. A007953 Digital sum (i.e. sum of digits) of n. A159463 Numbers n with property that sod(n^3) = 6^3.

Programs

  • Mathematica
    Select[Range[10^6],Total[IntegerDigits[#^3]]==125&] (* Harvey P. Dale, Jun 29 2022 *)
  • PARI
    isok(n) = sumdigits(n^3) == 125; \\ Michel Marcus, Oct 16 2013

A159463 Numbers n with property that sod(n^3) = 6^3.

Original entry on oeis.org

3848163483, 4462569999, 4479677412, 4586158119, 4594661259, 4594665192, 4594700889, 4625720379, 4641588459, 5644008999, 5828410842, 5833034823, 5838252576, 5848025709, 6453471192, 6617331999, 6619097067, 6686657169, 7107126942, 7230291999, 7277907183
Offset: 1

Views

Author

Zak Seidov, Apr 12 2009

Keywords

Comments

Numbers n with property that A007953(n^3) = 6^3.

Examples

			3848163483^3 = 56984998629886989599887999587, 5+6+9+8+4+9+9+8+6+2+9+8+8+6+9+8+9+5+9+9+8+8+7+9+9+9+5+8+7 = 216 = 6^3.
		

Crossrefs

Cf. A054966 Numbers that are congruent to {0, 1, 8} mod 9. A054966 Possible sums of digits of cubes. A067075 a(n) = smallest number m such that the sum of the digits of m^3 is equal to n^3. A007953 Digital sum (i.e., sum of digits) of n.
Numbers n such that sum of digits of n^3 is k^3: A107679 (k=2), A290842 (k=3), A290843 (k=4), A159462 (k=5), this sequence (k=6).

Extensions

a(16)-a(21) from Seiichi Manyama, Aug 12 2017

A067074 a(n) = smallest cube m^3 such that the sum of the digits of m^3 is equal to n^3.

Original entry on oeis.org

0, 1, 8, 19683, 1693669888, 39677989979796875, 56984998629886989599887999587
Offset: 0

Views

Author

Amarnath Murthy, Jan 05 2002

Keywords

Comments

If n = 6*k, a(n) <= A272066(n^3/18). - Seiichi Manyama, Aug 12 2017

Examples

			a(3) = 19683 as it is the smallest cube whose digit sum = 27 = 3^3.
		

Crossrefs

Formula

a(n) = A067075(n)^3. - R. J. Mathar, Aug 23 2018

Extensions

Corrected by Stefan Steinerberger, Nov 09 2005, using existing corrections to A067075
a(0)=0 prepended by Seiichi Manyama, Aug 12 2017

A290843 Numbers k such that the sum of digits of k^3 is 4^3 = 64.

Original entry on oeis.org

1192, 1366, 1426, 1435, 1753, 1786, 1813, 1816, 1912, 1942, 1999, 2116, 2389, 2395, 2398, 2413, 2566, 2599, 2632, 2635, 2653, 2692, 2713, 2872, 2899, 2992, 3022, 3031, 3103, 3199, 3289, 3295, 3298, 3301, 3355, 3361, 3382, 3394, 3409, 3415, 3442, 3466, 3475
Offset: 1

Views

Author

Seiichi Manyama, Aug 12 2017

Keywords

Examples

			1192^3 = 1693669888, 1 + 6 + 9 + 3 + 6 + 6 + 9 + 8 + 8 + 8 = 64 = 4^3.
11*(10^(n+2) + 1) is a term for all n > 0. - _Altug Alkan_, Aug 12 2017
		

Crossrefs

Numbers k such that sum of digits of k^3 is m^3: A107679 (m=2), A290842 (m=3), this sequence (m=4), A159462 (m=5), A159463 (m=6).
Cf. A067075.

Programs

  • Mathematica
    Select[Range[3500],Total[IntegerDigits[#^3]]==64&] (* Harvey P. Dale, Aug 04 2019 *)
  • PARI
    isok(n) = sumdigits(n^3) == 64; \\ Altug Alkan, Aug 12 2017

A286650 a(n) is the smallest number m such that the sum of the digits of m^4 is equal to n^4.

Original entry on oeis.org

0, 1, 11, 1434, 1269681358
Offset: 0

Views

Author

Seiichi Manyama, Aug 15 2017

Keywords

Examples

			a(2) = 11 as 11^4 = 14641 is the smallest fourth power whose digit sum = 16 = 2^4.
		

Crossrefs

Cf. A000583 (n^4), A055565 (sum of digits of n^4).

Programs

  • PARI
    {a(n) = my(k=0); while(sumdigits(k^4) != n^4, k++); k}

A290842 Numbers k such that the sum of digits of k^3 is 3^3 = 27.

Original entry on oeis.org

27, 33, 36, 39, 42, 54, 57, 69, 72, 75, 78, 84, 87, 93, 105, 108, 111, 114, 135, 138, 147, 162, 165, 168, 174, 177, 219, 222, 225, 228, 231, 234, 258, 267, 270, 273, 276, 285, 291, 294, 312, 318, 321, 330, 342, 345, 348, 351, 360, 369, 381, 384, 390, 405, 417
Offset: 1

Views

Author

Seiichi Manyama, Aug 12 2017

Keywords

Comments

It is obvious that if k is in this sequence, then so is 10*k. Additionally, this sequence contains other infinite subsequences. For example, 10^(2*k) + 10^k + 1 is in this sequence for all k > 0. - Altug Alkan, Aug 12 2017

Examples

			27^3 = 19683, 1 + 9 + 6 + 8 + 3 = 27 = 3^3.
		

Crossrefs

Numbers k such that sum of digits of k^3 is m^3: A107679 (m=2), this sequence (m=3), A290843 (m=4), A159462 (m=5), A159463 (m=6).
Cf. A067075.

Programs

  • PARI
    isok(n) = sumdigits(n^3) == 27; \\ Altug Alkan, Aug 12 2017

A328364 a(n) is the smallest number m such that the sum of the digits of m^5 is equal to n^5.

Original entry on oeis.org

0, 1, 47, 13174539
Offset: 0

Views

Author

Seiichi Manyama, Oct 14 2019

Keywords

Examples

			a(2) = 47 as 47^5 = 229345007 is the smallest fifth power whose digit sum = 32 = 2^5.
		

Crossrefs

Cf. A000584 (n^5), A055566 (sum of digits of n^5).

Programs

  • PARI
    {a(n) = my(k=0); while(sumdigits(k^5) != n^5, k++); k}
Showing 1-9 of 9 results.