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 1-5 of 5 results.

A070248 Palindromic primes with digit sum 7.

Original entry on oeis.org

7, 151, 313, 10501, 11311, 30103, 1201021, 3001003, 100050001, 100131001, 101030101, 110111011, 111010111, 10000500001, 1100011100011, 1100101010011, 100020010020001
Offset: 1

Views

Author

Amarnath Murthy, May 05 2002

Keywords

Crossrefs

Programs

  • Mathematica
    Do[p = Join[ IntegerDigits[n], Reverse[ Drop[ IntegerDigits[n], -1]]]; q = Plus @@ p; If[ PrimeQ[ FromDigits[p]] && q == 7, Print[ FromDigits[p]]], {n, 1, 10^7}]

Extensions

Edited by Robert G. Wilson v, May 15 2002

A070249 Palindromic primes with digit sum 8.

Original entry on oeis.org

10601, 11411, 30203, 31013, 1022201, 1120211, 1300031, 3002003, 100060001, 103000301, 111020111, 300020003, 300101003, 10002220001, 10200200201, 10210001201, 1000030300001, 1021000001201, 1030000000301, 1101010101011
Offset: 1

Views

Author

Amarnath Murthy, May 05 2002

Keywords

Crossrefs

Programs

  • Mathematica
    Do[p = Join[ IntegerDigits[n], Reverse[ Drop[ IntegerDigits[n], -1]]]; q = Plus @@ p; If[ PrimeQ[ FromDigits[p]] && q == 8, Print[ FromDigits[p]]], {n, 1, 10^7}]
    Select[Prime[Range[1626*10^4]],Total[IntegerDigits[#]]==8&&PalindromeQ[#]&] (* The program generates the first 13 terms of the sequence. *) (* Harvey P. Dale, Jul 18 2022 *)

Extensions

Edited by Robert G. Wilson v, May 15 2002

A070250 Palindromic primes with digit sum 10.

Original entry on oeis.org

181, 12421, 30403, 1008001, 1114111, 1212121, 100161001, 100404001, 101060101, 101141101, 102040201, 102202201, 104000401, 130020031, 140000041, 10001610001, 10013031001, 10100600101, 10102220101, 10130003101
Offset: 1

Views

Author

Amarnath Murthy, May 05 2002

Keywords

Crossrefs

Programs

  • Mathematica
    Do[p = IntegerDigits[ Prime[n]]; If[ Plus @@ p == 10 && Reverse[p] == p, Print[ Prime[n]]], {n, 1, 10^10}]
    Select[Prime[Range[4607*10^5]],PalindromeQ[#]&&Total[IntegerDigits[#]]==10&] (* Harvey P. Dale, May 28 2023 *)

Extensions

Edited and extended by Robert G. Wilson v and Jason Earls, May 06 2002

A070831 Palindromic primes with digit sum = 11.

Original entry on oeis.org

191, 353, 13331, 1123211, 1221221, 1303031, 1311131, 3103013, 110232011, 111050111, 112030211, 112111211, 121111121, 130030031, 301111103, 10000900001, 10002520001, 10013131001, 10111311101, 10301110301
Offset: 1

Views

Author

Robert G. Wilson v, May 15 2002

Keywords

Comments

Conjecture: The sequence is unbounded.

Crossrefs

Programs

  • Mathematica
    Do[p = Join[ IntegerDigits[n], Reverse[ Drop[ IntegerDigits[n], -1]]]; q = Plus @@ p; If[ PrimeQ[ FromDigits[p]] && q == 11, Print[ FromDigits[p]]], {n, 1, 10^6}]

A344424 Numbers k such that A344423(k) is prime.

Original entry on oeis.org

3, 54, 58, 64, 70, 253, 438, 4255, 8770
Offset: 1

Views

Author

Felix Fröhlich, May 18 2021

Keywords

Comments

a(10) > 10000. - Hugo Pfoertner, May 19 2021

Examples

			A344423(3) = 100111001 is prime, so 3 is a term of the sequence.
		

Crossrefs

Programs

  • PARI
    is(n) = ispseudoprime(10^(2*n+2) + 111*10^n + 1)

Extensions

a(9) from Hugo Pfoertner, May 19 2021
Showing 1-5 of 5 results.