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 23 results. Next

A050673 a(n) is the smallest prime such that the number of primes produced according to rules stipulated in Honaker's A048853 is n.

Original entry on oeis.org

6983, 4409, 2, 97, 29, 23, 11, 13, 131, 101, 107, 1459, 1297, 1423, 15731, 13597, 105967, 249533, 1006391, 2391041, 10866913, 77538289, 107640251, 120988597, 119628479, 10168288073, 1812918883, 115829122963
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Comments

a(26) > 10^10. a(27) = 1812918883. a(n) > 10^10 for n >= 28. - Donovan Johnson, May 08 2010
a(29) > 1.9*10^11. - Giovanni Resta, Aug 14 2013

Crossrefs

Cf. A048853, first terms of A050663-A050672, A050662.

Programs

  • Maple
    A048853 := proc(n::integer) local resul,ddigs,d,c,tmp,tst ; resul := 0 ; ddigs := convert(n,base,10) ; for d from 1 to nops(ddigs) do for c from 0 to 9 do if c = 0 and d = nops(ddigs) then continue ; else if c <> op(d,ddigs) then tmp := [op(1..d-1,ddigs),c,op(d+1..nops(ddigs),ddigs)] ; tst := sum(op(i,tmp)*10^(i-1),i=1..nops(tmp)) ; if isprime(tst) then resul := resul+1 ; fi ; fi ; fi ; od : od ; RETURN(resul) ; end: A050673 := proc(n::integer) local i,p; for p from 1 to 10000000 do i := ithprime(p) ; if A048853(i) = n then RETURN(i) ; fi ; od ; RETURN(-1) ; end : for n from 1 to 90 do print(A050673(n)) ; od ; # R. J. Mathar, Apr 25 2006

Formula

A048853(a(n))=n. a(n) is prime. a(n)>=A050662(n). - R. J. Mathar, Apr 25 2006

Extensions

a(22)-a(25) from Donovan Johnson, May 08 2010
a(26) and a(28) from Giovanni Resta, Aug 14 2013

A050662 a(n) is smallest number such that number of primes produced according to rules stipulated in Honaker's A048853 is n.

Original entry on oeis.org

90, 20, 2, 1, 29, 23, 11, 13, 117, 101, 107, 387, 177, 357, 1001, 4221, 10759, 11487, 42497, 42189, 317721, 984417, 344253, 1851759, 14040341, 15848679, 125367697, 139367847, 1044394659, 2214409197, 2909053719, 14485875423, 1167555543, 111738007953
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Comments

a(32) > 10^10. a(33) = 1167555543. a(34) > 10^10. - Donovan Johnson, May 08 2010
a(35) > 3*10^11. - Oscar Volpatti, Aug 06 2020

Crossrefs

Cf. A048853, first terms of A050652-A050661, A050673.

Programs

  • Maple
    A048853 := proc(n::integer) local resul,ddigs,d,c,tmp ; resul := 0 ; ddigs := convert(n,base,10) ; for d from 1 to nops(ddigs) do for c from 0 to 9 do if c = 0 and d = nops(ddigs) then continue ; else if c <> op(d,ddigs) then tmp := [op(1..d-1,ddigs),c,op(d+1..nops(ddigs),ddigs)] ; tst := sum(op(i,tmp)*10^(i-1),i=1..nops(tmp)) ; if isprime(tst) then resul := resul+1 ; fi ; fi ; fi ; od : od ; RETURN(resul) ; end: A050662 := proc(n::integer) local i; for i from 1 to 10000000 do if A048853(i) = n then RETURN(i) ; fi ; od ; RETURN(-1) ; end : for n from 1 to 90 do print(A050662(n)) ; od ; # R. J. Mathar, Apr 25 2006

Extensions

a(25)-a(31) and a(33) from Donovan Johnson, May 08 2010
a(32) and a(34) from Oscar Volpatti, Aug 06 2020

A050652 Numbers n such that number of primes produced according to rules stipulated in Honaker's A048853 is 1.

Original entry on oeis.org

90, 92, 94, 95, 96, 98, 110, 112, 114, 115, 116, 118, 120, 122, 124, 125, 126, 128, 140, 142, 144, 145, 146, 148, 180, 182, 184, 185, 186, 188, 210, 212, 214, 215, 216, 218, 240, 242, 244, 245, 246, 248, 290, 292, 294, 295, 296, 298, 300, 302, 304, 305, 306
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Examples

			Altering a(1)=90 gives 1 prime: 97.

Crossrefs

Cf. A048853, A050662, A050663.

A050661 Numbers n such that number of primes produced according to rules stipulated in Honaker's A048853 is 10.

Original entry on oeis.org

101, 111, 119, 139, 141, 159, 161, 169, 171, 191, 261, 291, 309, 327, 363, 409, 411, 429, 459, 507, 527, 567, 573, 583, 597, 651, 671, 707, 763, 767, 777, 857, 917, 977, 1003, 1009, 1013, 1019, 1031, 1049, 1069, 1091, 1127, 1131, 1159, 1161, 1167, 1179
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Examples

			Altering a(2)=111 gives 10 primes: 211, 311, 811, 911, 101, 131, 151, 181, 191 and 113.

Crossrefs

Cf. A048853, A050662, A050672.

A050663 Primes p such that number of primes produced according to rules stipulated in Honaker's A048853 is 1.

Original entry on oeis.org

6983, 46769, 97039, 97919, 98519, 99721, 134129, 283961, 321187, 373229, 440497, 444623, 448519, 472261, 492839, 504991, 509557, 553919, 575009, 578923, 591937, 605707, 623107, 629339, 649559, 687847, 714037, 744019, 756011, 791081, 806671
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Examples

			Altering a(1)=6983 gives 1 prime: 6883.

Crossrefs

Cf. A048853, A050673, A050652.

A050672 Primes p such that number of primes produced according to rules stipulated in Honaker's A048853 is 10.

Original entry on oeis.org

101, 139, 191, 409, 857, 977, 1009, 1013, 1019, 1031, 1049, 1069, 1091, 1231, 1409, 1429, 1451, 1481, 1487, 1493, 1523, 1667, 1733, 1753, 1787, 1789, 1831, 1877, 1879, 1931, 1933, 1999, 2069, 2111, 2243, 2287, 2293, 2351, 2381, 2417, 2447, 2477, 2539
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Examples

			Altering a(1)=101 gives 10 primes: 401, 601, 701, 131, 151, 181, 191, 103, 107 and 109.

Crossrefs

Cf. A048853, A050673, A050661.

A050653 Numbers n such that number of primes produced according to rules stipulated in Honaker's A048853 is 2.

Original entry on oeis.org

20, 22, 24, 25, 26, 28, 30, 32, 34, 35, 36, 38, 50, 52, 54, 55, 56, 58, 60, 62, 64, 65, 66, 68, 80, 82, 84, 85, 86, 88, 150, 152, 154, 155, 156, 158, 160, 162, 164, 165, 166, 168, 170, 172, 174, 175, 176, 178, 230, 232, 234, 235, 236, 238, 250, 252, 254, 255, 256
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Examples

			Altering a(1)=20 gives 2 primes: 23 and 29.

Crossrefs

Cf. A048853, A050662, A050664.

A050654 Numbers n such that number of primes produced according to rules stipulated in Honaker's A048853 is 3.

Original entry on oeis.org

2, 3, 5, 7, 40, 42, 44, 45, 46, 48, 70, 72, 74, 75, 76, 78, 130, 132, 134, 135, 136, 138, 220, 222, 224, 225, 226, 228, 310, 312, 314, 315, 316, 318, 430, 432, 434, 435, 436, 438, 460, 462, 464, 465, 466, 468, 610, 612, 614, 615, 616, 618, 640, 642, 644, 645
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Examples

			Altering a(17)=130 gives 3 primes: 131, 137 and 139.

Crossrefs

Cf. A048853, A050662, A050665.

A050655 Numbers n such that number of primes produced according to rules stipulated in Honaker's A048853 is 4.

Original entry on oeis.org

1, 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 97, 100, 102, 104, 105, 106, 108, 190, 192, 194, 195, 196, 198, 389, 659, 689, 743, 820, 822, 824, 825, 826, 828, 953, 989, 1480, 1482, 1484, 1485, 1486, 1488, 1870, 1872, 1874, 1875, 1876, 1878, 2080, 2082, 2084, 2085
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Examples

			Altering a(13)=100 gives 4 primes: 101, 103, 107 and 109.

Crossrefs

Cf. A048853, A050662, A050666.

A050656 Numbers n such that number of primes produced according to rules stipulated in Honaker's A048853 is 5.

Original entry on oeis.org

29, 31, 37, 59, 61, 67, 89, 269, 321, 331, 443, 487, 503, 521, 569, 571, 589, 599, 629, 733, 751, 761, 773, 811, 903, 919, 983, 1139, 1141, 1291, 1303, 1319, 1511, 1567, 1641, 1777, 1847, 2071, 2179, 2473, 2579, 2633, 2671, 2707, 2773, 2921, 2927, 2981
Offset: 1

Views

Author

Patrick De Geest, Jul 15 1999

Keywords

Examples

			Altering a(9)=321 gives 5 primes: 421, 521, 821, 311 and 331.

Crossrefs

Cf. A048853, A050662, A050667.
Showing 1-10 of 23 results. Next

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