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 15 results. Next

A102185 Iccanobirt semiprime indices (15 of 15): Indices of semiprime numbers in A102125.

Original entry on oeis.org

5, 15, 16, 19, 20, 21, 22, 24, 28, 29, 35, 38, 44, 54, 58, 59, 72, 84, 106, 108, 137, 145, 174, 227, 238, 253, 258, 362, 363, 371, 388
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Crossrefs

Cf. A001358, A102125, A102171-A102184, A102205.

Formula

A102125(a(n)) = A102205(n).

Extensions

a(24)-a(27) from Robert Price, Nov 11 2018
Offset changed to 1 and a(28)-a(31) from Jinyuan Wang, Aug 15 2021

A102191 Iccanobirt semiprimes (1 of 15): Semiprime numbers in A102111.

Original entry on oeis.org

4, 185, 1135955, 550783729, 10755767351826313, 885150880428474601, 145045760838001005739, 276700469046311728441, 17906534239981723909956235510218343, 23104799226903739899579090259021365554, 504198286800075916303995704410366363448429, 2363732899718211729861685511671459865604449872085443
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Crossrefs

Cf. A001358, A102111, A102192-A102205.

Formula

a(n) = A102111(A102171(n)).

Extensions

Offset changed to 1 and more terms from Jinyuan Wang, Jul 31 2021

A102192 Iccanobirt semiprimes (2 of 15): Semiprime numbers in A102112.

Original entry on oeis.org

4, 62, 885229, 1246986214, 6411178063, 12726051979, 107213343921600529, 2147942208584833933, 10354578286673927897, 58980651512479169892243191, 2180545853785440701368914883, 16670504896204082873702933353, 1970627022928300844150934760319, 8848738313604306954943751816182969
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Crossrefs

Cf. A001358, A102112, A102191-A102205.

Programs

  • Mathematica
    nxt[{a_,b_,c_}]:={b,c,a+IntegerReverse[b]+c};Select[NestList[nxt,{0,0,1},100][[All,1]],PrimeOmega[#]==2&] (* Harvey P. Dale, Jul 11 2021 *)

Formula

a(n) = A102112(A102172(n)).

Extensions

Offset changed to 1 and more terms from Jinyuan Wang, Aug 08 2021

A102195 Iccanobirt semiprimes (5 of 15): Semiprime numbers in A102115.

Original entry on oeis.org

4, 779, 1138, 57415, 77633, 55486847, 1073911003, 3317721397, 1060433508262511, 71024113009688593314067, 11974445409544006175987023, 1076202964567631961558639609002933, 33696092853645518103687453241761538, 4617443279524324394317910914689160360213
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Links

Crossrefs

Cf. A001358, A102115, A102191-A102205.

Programs

  • Mathematica
    nxt[{a_,b_,c_}]:={b,c,Total[FromDigits/@Reverse/@IntegerDigits[{a,c}]]+b};Select[NestList[nxt,{0,0,1},120][[;;,1]],PrimeOmega[#]==2&] (* Harvey P. Dale, Mar 02 2025 *)

Formula

a(n) = A102115(A102175(n)).

Extensions

Offset changed to 1 and a(14) from Jinyuan Wang, Aug 12 2021

A102204 Iccanobirt semiprimes (14 of 15): Semiprime numbers in A102124.

Original entry on oeis.org

4, 581, 72451, 789881, 92901661, 80528542, 89682664933, 36628597458132971, 8945663663547804571, 28420671229606403893, 9998333571760746216777082258511, 87894839031505105300173553652227351, 395837506159704761826300702753027374, 83686138907389068924615617486884954496701274604545267754241
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Crossrefs

Cf. A001358, A102124, A102184, A102191-A102205.

Formula

a(n) = A102124(A102184(n)).

Extensions

Offset changed to 1 and more terms from Jinyuan Wang, Aug 15 2021

A102193 Iccanobirt semiprimes (3 of 15): Semiprime numbers in A102113.

Original entry on oeis.org

4, 62, 203, 12622, 1587497, 1868619823, 90661877021812382699758, 1538984096138042194598749, 176790247727720247287001192437, 2726402749746956241622994522641, 186786483736027016457092821075933, 273198997240107723863576578753631, 32049985148080783062944679479294696996434
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Crossrefs

Cf. A001358, A102113, A102191-A102205.

Formula

a(n) = A102113(A102173(n)).

Extensions

Offset changed to 1 and more terms from Jinyuan Wang, Aug 10 2021

A102194 Iccanobirt semiprimes (4 of 15): Semiprime numbers in A102114.

Original entry on oeis.org

4, 185, 24361, 921717757, 1920600983, 9086150726, 913083071429, 2014396919113, 63178492261555241, 9004315140856495091, 63162327910155025982578333897, 27030665951900873389459251276162714636270614605, 71854905634496924458553731195035575408569457647039865953
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Crossrefs

Cf. A001358, A102114, A102191-A102205.

Formula

a(n) = A102114(A102174(n)).

Extensions

Offset changed to 1 and a(13) from Jinyuan Wang, Aug 10 2021

A102196 Iccanobirt semiprimes (6 of 15): Semiprime numbers in A102116.

Original entry on oeis.org

4, 62, 18409, 11871383, 179446253401, 55485890942935, 8760033628867763034703, 77397904424005721701931992165, 117620535110076552813927714538053562565219253501365446, 57053214293426832976128532148240906999130287862801348038, 3084400686317650617690846479039523322373660299445872156438
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Crossrefs

Cf. A001358, A102116, A102191-A102205.

Formula

a(n) = A102116(A102176(n)).

Extensions

Offset changed to 1 and more terms from Jinyuan Wang, Aug 12 2021

A102197 Iccanobirt semiprimes (7 of 15): Semiprime numbers in A102117.

Original entry on oeis.org

4, 62, 1350266, 7217219419, 662282997049, 131048548574311, 1476501837943501, 77398992743877949, 1009160086034826303, 7334718374224277375323, 267139368935075847112946291, 149235809291913788071835702010683, 1385662433217897970940689446154295119
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Crossrefs

Cf. A001358, A102117, A102191-A102205.

Formula

a(n) = A102117(A102177(n)).

Extensions

Offset changed to 1 and a(13) from Jinyuan Wang, Aug 12 2021

A102198 Iccanobirt semiprimes (8 of 15): Semiprime numbers in A102118.

Original entry on oeis.org

4, 26, 86, 8149, 63071, 16297, 649051, 58252941851, 92725334137, 1053497381056741, 1278670308661982, 94977834729989377, 670970457022641744643, 875040780930863483219, 717513198454659455769232618, 5543447679090248342657818634097933227550696536461
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Crossrefs

Cf. A001358, A102118, A102191-A102205.

Formula

a(n) = A102118(A102178(n)).

Extensions

Offset changed to 1 and more terms from Jinyuan Wang, Aug 14 2021
Showing 1-10 of 15 results. Next

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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