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.

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A076165 Numbers n such that sum of cubes of even digits of n equals sum of cubes of odd digits of n.

Original entry on oeis.org

14467, 14476, 14647, 14674, 14746, 14764, 16447, 16474, 16744, 17446, 17464, 17644, 41467, 41476, 41647, 41674, 41746, 41764, 44167, 44176, 44617, 44671, 44716, 44761, 46147, 46174, 46417, 46471, 46714, 46741, 47146, 47164, 47416
Offset: 1

Views

Author

Zak Seidov, Nov 01 2002

Keywords

Comments

Minimal number of digits in n is 5.
n such that sum of even digits equals sum of odd digits in A036301.

Examples

			14467 is OK because 1^3+7^3=4^3+4^3+6^3.
		

Crossrefs

Programs

  • Mathematica
    oeQ[n_]:=Module[{idn = IntegerDigits[n]},Total[Select[idn, OddQ]^3] == Total[Select[idn, EvenQ]^3]]; Select[Range[100000],oeQ] (* Harvey P. Dale, Sep 23 2011 *)
  • PARI
    ok(n)={my(v=digits(n)); sum(i=1, #v, v[i]^3*if(v[i]%2, 1, -1))==0} \\ Andrew Howroyd, Dec 10 2018

A076166 Primes p such that sum of cubes of even digits of p equals sum of cubes of odd digits of p.

Original entry on oeis.org

16447, 41467, 41647, 44617, 46147, 46471, 76441, 114451, 144511, 146407, 404167, 404671, 414607, 415141, 416407, 440761, 441607, 451411, 460147, 460417, 461407, 470461, 476041, 476401, 541141, 610447, 640741, 644107, 644701, 647401, 704461, 740461, 746041, 764041
Offset: 1

Views

Author

Zak Seidov, Nov 01 2002

Keywords

Comments

Minimal number of digits in p is 5. n such that sum of even digits equals sum of odd digits in A036301.
To find terms of this sequence, one could look at zerofree positive integers having the criterion on sum of cubes of digits. Then permute the digits to see which are prime. Using those digits with 0 and permuting then only needs the check on primality. - David A. Corneth, Dec 11 2018

Examples

			16447 is OK because 1^3 + 7^3 = 6^3 + 4^3 + 4^3.
14467 has digits in nondecreasing order (is zerofree). Of the 60 permutations, 16447, 41467, 41647, 44617, 46147, 46471, 76441 are prime. - _David A. Corneth_, Dec 11 2018
		

Crossrefs

Subsequence of A076165.

Programs

  • Mathematica
    oeQ[n_]:=Module[{idn = IntegerDigits[n]}, Total[Select[idn, OddQ]^3] == Total[ Select[idn, EvenQ]^3]]; Select[Range[100000], PrimeQ[#] && oeQ[#] &] (* Amiram Eldar, Dec 10 2018 after Harvey P. Dale at A076165 *)
  • PARI
    isok(p) = isprime(p) && (d=digits(p)) && (sum(i=1, #d, d[i]^3*if(d[i]%2, 1, -1))==0); \\ Michel Marcus, Dec 13 2018

A076167 Primes p such that sum of even digits of p equals sum of odd digits of p.

Original entry on oeis.org

211, 431, 853, 1021, 1087, 1201, 1223, 1289, 1447, 1627, 2011, 2213, 2617, 2671, 2819, 2837, 3041, 3221, 3467, 4013, 4637, 4673, 4691, 5443, 5623, 5689, 5869, 6217, 6271, 6473, 6491, 7283, 7621, 7643, 7687, 7823, 7867, 8017, 8053, 8219, 8237, 8273
Offset: 1

Views

Author

Zak Seidov, Nov 01 2002

Keywords

Comments

Primes in A036301.

Examples

			2671 is OK because 2+6=7+1.
		

Crossrefs

Intersection of A000040 and A036301,
Cf. A111309.

Programs

  • Maple
    f:= proc(n) local Lo,Le;
      Lo,Le:= selectremove(type,convert(n,base,10),odd);
      abs(convert(Lo,`+`)-convert(Le,`+`))
    end proc:
    select(t -> f(t) = 0, [seq(ithprime(i),i=1..10000)]); # Robert Israel, Nov 13 2024
  • Mathematica
    soeQ[n_]:=2*Total[Select[(x=IntegerDigits[n]),OddQ[#]&]]==Total[x]; Select[Prime[Range[1050]],soeQ[#]&] (* Jayanta Basu, May 23 2013 *)
    Cases[{Total@# &/@GatherBy[IntegerDigits@#,OddQ], #}&/@
    Prime@Range@3000, {{x_, x_}, y_} :> y] (* Hans Rudolf Widmer, Jul 26 2024 *)

A103829 Sum of even digits less than sum of odd digits.

Original entry on oeis.org

0, 2, 4, 6, 8, 12, 14, 16, 18, 20, 21, 22, 24, 26, 28, 34, 36, 38, 40, 41, 42, 43, 44, 46, 48, 56, 58, 60, 61, 62, 63, 64, 65, 66, 68, 78, 80, 81, 82, 83, 84, 85, 86, 87, 88, 102, 104, 106, 108, 114, 116, 118, 120, 122, 124, 126, 128, 136, 138, 140, 141, 142, 144, 146
Offset: 1

Views

Author

Zak Seidov, Feb 17 2005

Keywords

Comments

0 is assumed as even digit: A005843, A004275, A007928. Sum of even digits equals sum of odd digits A036301.

Crossrefs

Programs

  • Mathematica
    Select[Range[300], Plus@@Select[IntegerDigits[ # ], OddQ]
    				

A103848 Numbers n such that sum of even digits of n is larger than sum of odd digits.

Original entry on oeis.org

1, 3, 5, 7, 9, 10, 11, 13, 15, 17, 19, 23, 25, 27, 29, 30, 31, 32, 33, 35, 37, 39, 45, 47, 49, 50, 51, 52, 53, 54, 55, 57, 59, 67, 69, 70, 71, 72, 73, 74, 75, 76, 77, 79, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 103, 105, 107, 109, 110, 111, 113, 115, 117, 119
Offset: 1

Views

Author

Zak Seidov, Feb 18 2005

Keywords

Comments

Sum of even digits equals sum of odd digits => A036301. Sum of even digits less than sum of odd digits => A103829

Crossrefs

Programs

  • Mathematica
    Select[Range[300], Plus@@Select[IntegerDigits[ # ], OddQ]>Plus@@Select[IntegerDigits[ # ], EvenQ]&]

Extensions

Mathematica program corrected by Harvey P. Dale, Oct 10 2024

A303269 Sum of squares of odd digits minus sum of squares of even digits of n.

Original entry on oeis.org

0, 1, -4, 9, -16, 25, -36, 49, -64, 81, 1, 2, -3, 10, -15, 26, -35, 50, -63, 82, -4, -3, -8, 5, -20, 21, -40, 45, -68, 77, 9, 10, 5, 18, -7, 34, -27, 58, -55, 90, -16, -15, -20, -7, -32, 9, -52, 33, -80, 65, 25, 26, 21, 34, 9, 50, -11, 74, -39, 106, -36, -35, -40, -27
Offset: 0

Views

Author

M. F. Hasler, May 18 2018

Keywords

Comments

Up to 10^4, resp. 10^5, there are 5824, resp. 59316, positive terms. All terms from a(1) to a(11111) are nonzero: see A076164 for indices of zeros.

Crossrefs

Programs

  • PARI
    A303269(n)=-vecsum(apply(d->d^2*(-1)^d,digits(n)))

A341003 Numbers whose sum of even digits and sum of odd digits differ by 2.

Original entry on oeis.org

2, 11, 20, 101, 110, 114, 123, 132, 136, 141, 145, 154, 158, 163, 167, 176, 185, 189, 198, 200, 213, 231, 312, 316, 321, 334, 338, 343, 356, 361, 365, 378, 383, 387, 411, 415, 433, 451, 514, 518, 536, 541, 558, 563, 581, 585, 613, 617, 631, 635, 653, 671, 716, 738, 761, 783
Offset: 1

Views

Author

Eric Angelini and Carole Dubois, Feb 02 2021

Keywords

Crossrefs

Cf. A036301 (sums are equal), A341002 to A341010 (sums differ by 1 to 9).

Programs

  • Mathematica
    Select[Range[1000], Abs[Plus @@ Select[(d = IntegerDigits[#]), OddQ] - Plus @@ Select[d, EvenQ]] == 2 &] (* Amiram Eldar, Feb 02 2021 *)

A341004 Numbers whose sum of even digits and sum of odd digits differ by 3.

Original entry on oeis.org

3, 14, 25, 30, 36, 41, 47, 52, 58, 63, 69, 74, 85, 96, 104, 111, 122, 140, 205, 212, 221, 227, 234, 243, 249, 250, 256, 265, 272, 278, 287, 294, 300, 306, 324, 342, 360, 401, 407, 410, 423, 429, 432, 445, 454, 467, 470, 476, 489, 492, 498, 502, 508, 520, 526, 544, 562, 580
Offset: 1

Views

Author

Eric Angelini and Carole Dubois, Feb 02 2021

Keywords

Crossrefs

Cf. A036301 (sums are equal), A341002 to A341010 (sums differ by 1 to 9).

Programs

  • Mathematica
    Select[Range[1000], Abs[Plus @@ Select[(d = IntegerDigits[#]), OddQ] - Plus @@ Select[d, EvenQ]] == 3 &] (* Amiram Eldar, Feb 02 2021 *)

A341005 Numbers whose sum of even digits and sum of odd digits differ by 4.

Original entry on oeis.org

4, 13, 22, 31, 40, 103, 116, 125, 130, 138, 147, 152, 161, 169, 174, 183, 196, 202, 215, 220, 233, 251, 301, 310, 318, 323, 332, 345, 354, 367, 376, 381, 389, 398, 400, 417, 435, 453, 471, 512, 521, 534, 543, 556, 565, 578, 587, 611, 619, 637, 655, 673, 691, 714, 736, 741, 758
Offset: 1

Views

Author

Eric Angelini and Carole Dubois, Feb 02 2021

Keywords

Crossrefs

Cf. A036301 (sums are equal), A341002 to A341010 (sums differ by 1 to 9).
Cf. A071650 (difference between sum of even and sum of odd digits).

Programs

  • Mathematica
    Select[Range[1000], Abs[Plus @@ Select[(d = IntegerDigits[#]), OddQ] - Plus @@ Select[d, EvenQ]] == 4 &] (* Amiram Eldar, Feb 02 2021 *)
  • Python
    def ok(n):
      sums = [0, 0]
      for d in str(n): sums[d in "13579"] += int(d)
      return abs(sums[0] - sums[1]) == 4
    print(list(filter(ok, range(759)))) # Michael S. Branicky, Apr 13 2021

A341006 Numbers whose sum of even digits and sum of odd digits differ by 5.

Original entry on oeis.org

5, 16, 27, 38, 49, 50, 61, 72, 83, 94, 106, 113, 124, 131, 142, 160, 207, 214, 229, 236, 241, 258, 263, 270, 285, 292, 308, 311, 326, 344, 362, 380, 409, 412, 421, 434, 443, 456, 465, 478, 487, 490, 500, 528, 546, 564, 582, 601, 610, 623, 632, 645, 654, 667, 676, 689, 698, 702
Offset: 1

Views

Author

Eric Angelini and Carole Dubois, Feb 02 2021

Keywords

Crossrefs

Cf. A036301 (sums are equal), A341002 to A341010 (sums differ by 1 to 9).

Programs

  • Mathematica
    Select[Range[1000], Abs[Plus @@ Select[(d = IntegerDigits[#]), OddQ] - Plus @@ Select[d, EvenQ]] == 5 &] (* Amiram Eldar, Feb 02 2021 *)
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