Rajesh Bhowmick - cp's OEIS frontend

User: Rajesh Bhowmick

Rajesh Bhowmick has authored 2 sequences.

A164967 Sequential primes built off of 1.

1, 13, 137, 13711, 1371113, 137111329, 13711132937, 13711132937113, 13711132937113307, 13711132937113307401, 13711132937113307401463, 13711132937113307401463509, 13711132937113307401463509541, 13711132937113307401463509541701

Offset: 1

Rajesh Bhowmick, Jan 14 2012

Begin with a 'seed' number, in this case a(1) = 1. Then a(n) is the concatenation of a(n-1) and some prime greater than any prime previously used to create a new prime number. Such a sequence is called a 'sequential prime' sequence.

Robert G. Wilson v, Table of n, a(n) for n = 1..100

Cf. A074336.

p = 3; f[n_] := Block[{}, While[q = n*10^Floor[1 + Log10[p]] + p; !PrimeQ[q], p = NextPrime[p]]; p = NextPrime[p]; q]; NestList[f, 1, 14] (* Robert G. Wilson v, Jan 14 2012 *)

Edited and extended by Robert G. Wilson v, Jan 14 2012

A203024 Numbers a = b + c where a, b, and c contain the same decimal digits.

Original entry on oeis.org

0, 954, 2961, 4932, 5013, 5022, 5031, 5238, 5823, 6147, 6417, 7614, 7641, 8235, 8523, 9045, 9108, 9180, 9324, 9504, 9540, 9594, 9612, 9684, 9774, 9864, 9954, 20961, 21150, 21501, 24831, 24921, 25011, 26901, 27810, 28107, 28314, 29016, 29214, 29610, 29691, 29961

Offset: 1

Rajesh Bhowmick, Dec 28 2011

987654321 and 9876543210 are members (987654321 = 123456789 + 864197532, 9876543210 = 1234567890 + 8641975320).

			954 is in the sequence since 954 = 459 + 495.

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

is(n)=my(v=vecsort(Vec(Str(n))));for(b=eval(concat(v)), n\2, if(vecsort(Vec(Str(b)))==v && vecsort(Vec(Str(n-b)))==v, return(1)));0 \\ Charles R Greathouse IV, Dec 28 2011

a(2)-a(42) from Charles R Greathouse IV, Dec 28 2011

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User: Rajesh Bhowmick

A164967 Sequential primes built off of 1.

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