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.

A071128 Squares which repeat with at least two full periods when written in base 2.

Original entry on oeis.org

36, 1849, 6241, 29929, 418609, 672400, 1320201, 7458361, 28121809, 119355625, 302794801, 386554921, 1211179204, 1277991001, 1967188609, 5111964004, 7681646025, 30542106169, 73073443041, 79698371481, 91424593225, 120297291921, 292293772164, 318793485924
Offset: 1

Views

Author

Erich Friedman, May 28 2002

Keywords

Examples

			173^2 = 29929 = 1110100|1110100|1 in base 2.
		

Crossrefs

Cf. A071129 (base 3) - A071135 (base 9), A069919 (base 10).

Programs

  • Mathematica
    psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t  b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[2, #] & /@ Range[32]) (* Giovanni Resta, Aug 01 2018 *)

Extensions

Missing a(13), a(17), and a(21) from Giovanni Resta, Aug 01 2018

A071135 Squares which repeat with at least two full periods when written in base 9.

Original entry on oeis.org

557904400, 1255284900, 2231617600, 508239242281, 110723679691024, 267200559990920521, 4624943568803015273104, 89426738951269414045129, 106343953870710063227329, 141828621071731373745001, 153228095100765507880225, 155946118585671902125225
Offset: 1

Views

Author

Erich Friedman, May 28 2002

Keywords

Examples

			23620^2 = 557904400 = 13857|13857 in base 9.
712909^2 = 508239242281 = 171676|171676|1 in base 9.
		

Crossrefs

Cf. A071128 (base 2) - A071134 (base 8), A069919 (base 10).

Programs

  • Mathematica
    psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t  b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[9, #] & /@ Range[10]) (* Giovanni Resta, Aug 01 2018 *)

Extensions

a(5)-a(12) from Giovanni Resta, Aug 01 2018

A116502 Squares with structure dmdmd, where d is a single digit and m a string of digits.

Original entry on oeis.org

69696, 56722567225, 95540955409, 1108033241108033241, 1220096161220096161, 4312080784312080784, 4432132964432132964, 4880384644880384644, 9024307889024307889, 9972299169972299169, 946308825294630882529, 11542927396115429273961, 46171709584461717095844
Offset: 1

Views

Author

Giovanni Resta, Feb 18 2006

Keywords

Examples

			309097^2 = a(3) = 9[5540]9[5540]9.
		

Crossrefs

Programs

  • Mathematica
    w={}; Do[s = Reduce[(1 + 10^(1+e) + 100^(1+e)) d + 10 (1+10^(1+e)) x == y^2 && 0 <= x < 10^e && y>0, {x,y}, Integers]; If[s =!= False, w = Union[w, y^2 /. List@ ToRules@ s]], {e, 12}, {d, 9}]; w (* Giovanni Resta, Aug 01 2018 *)

Formula

a(n) = A116501(n)^2.

Extensions

a(11)-a(13) from Giovanni Resta, Aug 01 2018

A071129 Squares which repeat with at least two full periods when written in base 3.

Original entry on oeis.org

4, 121, 841, 6889, 60025, 62001, 68644, 534361, 540225, 1042441, 4791721, 4809249, 20811844, 43072969, 43125489, 43283241, 387499225, 387656721, 388129401, 567725929, 713584369, 1255284900, 2231617600, 3487020601, 3487493025, 3488910489, 31381768201
Offset: 1

Views

Author

Erich Friedman, May 28 2002

Keywords

Examples

			11^2 = 121 = 1|1|1|1|1 in base 3.
249^2 = 62001 = 1001|1001|100 in base 3.
		

Crossrefs

Cf. A071128 (base 2) - A071135 (base 9), A069919 (base 10).

Programs

  • Mathematica
    psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t  b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[3, #] & /@ Range[20]) (* Giovanni Resta, Aug 01 2018 *)

Extensions

a(25)-a(27) from Giovanni Resta, Aug 01 2018

A071134 Squares which repeat with at least two full periods when written in base 8.

Original entry on oeis.org

9, 36, 6241, 116964, 418609, 28121809, 477247716, 1277991001, 1967188609, 5111964004, 7681646025, 73073443041, 79698371481, 91424593225, 120297291921, 292293772164, 318793485924, 1954689202404, 5429696889241, 5480313774049, 21718787556964, 21921255096196
Offset: 1

Views

Author

Erich Friedman, May 28 2002

Keywords

Examples

			647^2 = 418609 = 146|146|1 in base 8.
21846^2 = 477247716 = 34344|34344 in base 8.
		

Crossrefs

Cf. A071128 (base 2) - A071135 (base 9), A069919 (base 10).

Programs

  • Mathematica
    psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t  b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[8, #] & /@ Range[11]) (* Giovanni Resta, Aug 01 2018 *)

Extensions

Missing a(18) and more terms from Giovanni Resta, Aug 01 2018

A071130 Squares which repeat with at least two full periods when written in base 4.

Original entry on oeis.org

6241, 378225, 672400, 1320201, 28121809, 302794801, 386554921, 1211179204, 7681646025, 73073443041, 79698371481, 91424593225, 120297291921, 292293772164, 318793485924, 657660987369, 1521820771641, 18145972716481, 72583890865924, 163313754448329
Offset: 1

Views

Author

Erich Friedman, May 28 2002

Keywords

Examples

			79^2 = 6241 = 120|120|1 in base 4.
615^2 = 378225 = 11301|11301 in base 4.
		

Crossrefs

Cf. A071128 (base 2) - A071135 (base 9), A069919 (base 10).

Programs

  • Mathematica
    psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t  b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[4, #] & /@ Range[16]) (* Giovanni Resta, Aug 01 2018 *)

Extensions

a(16)-a(20) from Giovanni Resta, Aug 01 2018

A071131 Squares which repeat with at least two full periods when written in base 5.

Original entry on oeis.org

7056, 71824, 17380561, 10479821641, 1695422743056, 3046710023334121, 3484661204178361, 4238552821180561, 16390460540754756, 2341118082098985289, 49597060188790044841, 413921144300672743056, 931719854156507158681, 1149780956458574459881, 1254278391764733006841
Offset: 1

Views

Author

Erich Friedman, May 28 2002

Keywords

Examples

			268^2 = 71824 = 424|424|4 in base 5.
1302084^2 = 1695422743056 = 210234211|210234211 in base 5.
		

Crossrefs

Cf. A071128 (base 2) - A071135 (base 9), A069919 (base 10).

Programs

  • Mathematica
    psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t  b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[5, #] & /@ Range[15]) (* Giovanni Resta, Aug 01 2018 *)

Extensions

a(5)-a(15) from Giovanni Resta, Aug 01 2018

A071132 Squares which repeat with at least two full periods when written in base 6.

Original entry on oeis.org

5776, 190096, 6739216, 97990201, 241989136, 242611776, 3975176401, 8707875856, 8711608896, 14393520729, 25588481296, 39982002025, 57574082916, 95174101009, 149392299169, 313461135376, 313483530816, 380696404036, 4724628251641, 11284466503696, 11284600873536
Offset: 1

Views

Author

Erich Friedman, May 28 2002

Keywords

Examples

			76^2 = 5776 = 42|42|4 in base 6.
119973^2 = 14393520729 = 1034013|1034013 in base 6.
		

Crossrefs

Cf. A071128 (base 2) - A071135 (base 9), A069919 (base 10).

Programs

  • Mathematica
    psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t  b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[6, #] & /@ Range[13]) (* Giovanni Resta, Aug 01 2018 *)

Extensions

Missing a(12), a(13), a(16) and more terms from Giovanni Resta, Aug 01 2018

A071133 Squares which repeat with at least two full periods when written in base 7.

Original entry on oeis.org

16, 400, 900, 1600, 29584, 70627216, 394618225, 2214643600, 4982948100, 8858574400, 16052636601, 64210546404, 169556179984, 727092173809, 1120597967889, 2908368695236, 6543829564281, 6703226505481, 79822717134736, 407103419654416, 12766762698010000
Offset: 1

Views

Author

Erich Friedman, May 28 2002

Keywords

Examples

			19865^2 = 394618225 = 12531|12531|1 in base 7.
411772^2 = 169556179984 = 1515152|1515152 in base 7.
		

Crossrefs

Cf. A071128 (base 2) - A071135 (base 9), A069919 (base 10).

Programs

  • Mathematica
    psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t  b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[7, #] & /@ Range[12]) (* Giovanni Resta, Aug 01 2018 *)

Extensions

a(17)-a(21) from Giovanni Resta, Aug 01 2018
Showing 1-9 of 9 results.